<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with Wdesk from Workiva-->
<!--Copyright 2022 Workiva-->
<!--r:27ac5810-b177-4f73-9ff2-f9646800099c,g:7bffbb52-bd7e-47f4-b8ee-a5a3c31e9464-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:arcroleRef arcroleURI="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/arcrole/esma-arcrole-2018-11-21.xsd#wider-narrower"/>
  <link:roleRef roleURI="http://www.sanofi.com/role/tatdesvariationsdescapitauxpropres" xlink:type="simple" xlink:href="sny-2021-12-31.xsd#tatdesvariationsdescapitauxpropres"/>
  <link:definitionLink xlink:role="http://www.sanofi.com/role/tatdesvariationsdescapitauxpropres" xlink:type="extended" id="i6b86e6e4ff184f31a667995e44034c75_tatdesvariationsdescapitauxpropres">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_StatementOfChangesInEquityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Equity_5e7573a9-771f-4d26-b467-c75dd25fe922" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_Equity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_ifrs-full_Equity_5e7573a9-771f-4d26-b467-c75dd25fe922" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherComprehensiveIncome_117c73ee-54e7-4084-a7e2-9243db82e3b1" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherComprehensiveIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_ifrs-full_OtherComprehensiveIncome_117c73ee-54e7-4084-a7e2-9243db82e3b1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProfitLoss_3e8e8e85-6f99-48ca-87f5-e13c5650f946" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_ifrs-full_ProfitLoss_3e8e8e85-6f99-48ca-87f5-e13c5650f946" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ComprehensiveIncome_db6918de-eb43-49bc-9cb1-c8b3773c13e0" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ComprehensiveIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_ifrs-full_ComprehensiveIncome_db6918de-eb43-49bc-9cb1-c8b3773c13e0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DividendsRecognisedAsDistributionsToOwnersOfParent_56dcd514-9623-462c-8e1a-e8166095fd08" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DividendsRecognisedAsDistributionsToOwnersOfParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_ifrs-full_DividendsRecognisedAsDistributionsToOwnersOfParent_56dcd514-9623-462c-8e1a-e8166095fd08" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DividendsRecognisedAsDistributionsToNoncontrollingInterests_782a3fad-6494-4683-bea3-adff52b8bb7b" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DividendsRecognisedAsDistributionsToNoncontrollingInterests"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_ifrs-full_DividendsRecognisedAsDistributionsToNoncontrollingInterests_782a3fad-6494-4683-bea3-adff52b8bb7b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_PurchaseOfTreasuryShares_82a337df-ebe2-4051-ab8d-fb521e9f7e1f" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PurchaseOfTreasuryShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_ifrs-full_PurchaseOfTreasuryShares_82a337df-ebe2-4051-ab8d-fb521e9f7e1f" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncreaseDecreaseThroughExerciseOfOptions_014ab6ad-45ef-4a81-9fa6-53621a7b54b3" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IncreaseDecreaseThroughExerciseOfOptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_ifrs-full_IncreaseDecreaseThroughExerciseOfOptions_014ab6ad-45ef-4a81-9fa6-53621a7b54b3" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsEmissionDactionsGratuitesEtAttributionDefinitiveDactionsGratuitesExistantesCapitauxPropres_d0cc359f-cc83-4e69-bb11-10cfd14bdb2d" xlink:href="sny-2021-12-31.xsd#sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsEmissionDactionsGratuitesEtAttributionDefinitiveDactionsGratuitesExistantesCapitauxPropres"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsEmissionDactionsGratuitesEtAttributionDefinitiveDactionsGratuitesExistantesCapitauxPropres_d0cc359f-cc83-4e69-bb11-10cfd14bdb2d" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncreaseDecreaseThroughTreasuryShareTransactions_60226138-2d1c-42d1-a156-5bad677ba178" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IncreaseDecreaseThroughTreasuryShareTransactions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_ifrs-full_IncreaseDecreaseThroughTreasuryShareTransactions_60226138-2d1c-42d1-a156-5bad677ba178" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsValeurDesServicesObtenusDesSalariesCapitauxPropres_9569b62e-4adb-478c-8b48-6a4c2ccf9139" xlink:href="sny-2021-12-31.xsd#sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsValeurDesServicesObtenusDesSalariesCapitauxPropres"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsValeurDesServicesObtenusDesSalariesCapitauxPropres_9569b62e-4adb-478c-8b48-6a4c2ccf9139" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsEffetDimpotsLieALaLeveeDoptionsCapitauxPropres_5c64d7f7-27ac-4534-831d-4625cd789d14" xlink:href="sny-2021-12-31.xsd#sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsEffetDimpotsLieALaLeveeDoptionsCapitauxPropres"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsEffetDimpotsLieALaLeveeDoptionsCapitauxPropres_5c64d7f7-27ac-4534-831d-4625cd789d14" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AugmentationDiminutionParLeBiaisDautresVariationsLieesALemissionDactionsGratuitesCapitauxPropres_63b6abb5-65f3-43d9-9ef6-bb76cab8e9c6" xlink:href="sny-2021-12-31.xsd#sny_AugmentationDiminutionParLeBiaisDautresVariationsLieesALemissionDactionsGratuitesCapitauxPropres"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_sny_AugmentationDiminutionParLeBiaisDautresVariationsLieesALemissionDactionsGratuitesCapitauxPropres_63b6abb5-65f3-43d9-9ef6-bb76cab8e9c6" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncreaseDecreaseThroughChangesInOwnershipInterestsInSubsidiariesThatDoNotResultInLossOfControl_19cbd824-c330-49bb-a253-14b7657c4b71" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IncreaseDecreaseThroughChangesInOwnershipInterestsInSubsidiariesThatDoNotResultInLossOfControl"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_ifrs-full_IncreaseDecreaseThroughChangesInOwnershipInterestsInSubsidiariesThatDoNotResultInLossOfControl_19cbd824-c330-49bb-a253-14b7657c4b71" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncreaseDecreaseThroughTransfersAndOtherChangesEquity_2f4454a8-3638-4f08-9d63-5ea99a098343" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IncreaseDecreaseThroughTransfersAndOtherChangesEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_ifrs-full_IncreaseDecreaseThroughTransfersAndOtherChangesEquity_2f4454a8-3638-4f08-9d63-5ea99a098343" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsAugmentationDeCapitalReserveesAuxSalariesCapitauxPropres_2da9407d-8267-468e-8e8c-d80005125267" xlink:href="sny-2021-12-31.xsd#sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsAugmentationDeCapitalReserveesAuxSalariesCapitauxPropres"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsAugmentationDeCapitalReserveesAuxSalariesCapitauxPropres_2da9407d-8267-468e-8e8c-d80005125267" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AugmentationDiminutionParLeBiaisDautreVariationDesInteretsNonControlantsCapitauxPropres_9b35013e-9aed-4204-b7d7-7c57e38ded6a" xlink:href="sny-2021-12-31.xsd#sny_AugmentationDiminutionParLeBiaisDautreVariationDesInteretsNonControlantsCapitauxPropres"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_sny_AugmentationDiminutionParLeBiaisDautreVariationDesInteretsNonControlantsCapitauxPropres_9b35013e-9aed-4204-b7d7-7c57e38ded6a" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Equity_b16fcb5b-c361-448a-9fba-a8213b4530f7" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_Equity"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_StatementOfChangesInEquityTable_d4a5f4e5-cf9d-4565-8475-d4ea0b292587" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_StatementOfChangesInEquityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_10d6c952-1986-44a5-a1d1-969e89a7b4e3" xlink:to="loc_ifrs-full_StatementOfChangesInEquityTable_d4a5f4e5-cf9d-4565-8475-d4ea0b292587" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="scenario"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ComponentsOfEquityAxis_28f5f3ba-5965-4ec1-add7-f72ca6bf45e4" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ComponentsOfEquityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_StatementOfChangesInEquityTable_d4a5f4e5-cf9d-4565-8475-d4ea0b292587" xlink:to="loc_ifrs-full_ComponentsOfEquityAxis_28f5f3ba-5965-4ec1-add7-f72ca6bf45e4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_EquityMember_fea92f26-797b-416f-ba36-ebdaf83900fe" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_EquityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ComponentsOfEquityAxis_28f5f3ba-5965-4ec1-add7-f72ca6bf45e4" xlink:to="loc_ifrs-full_EquityMember_fea92f26-797b-416f-ba36-ebdaf83900fe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IssuedCapitalMember_e22cf808-9cda-432d-9eaf-742c7c49ff00" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IssuedCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EquityMember_fea92f26-797b-416f-ba36-ebdaf83900fe" xlink:to="loc_ifrs-full_IssuedCapitalMember_e22cf808-9cda-432d-9eaf-742c7c49ff00" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AdditionalPaidinCapitalMember_c7aee1eb-aa3d-4ca2-b0db-86dc91dd9593" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdditionalPaidinCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EquityMember_fea92f26-797b-416f-ba36-ebdaf83900fe" xlink:to="loc_ifrs-full_AdditionalPaidinCapitalMember_c7aee1eb-aa3d-4ca2-b0db-86dc91dd9593" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_TreasurySharesMember_b2d50b77-b5ce-4e8d-9aee-7859ecbda12e" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_TreasurySharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EquityMember_fea92f26-797b-416f-ba36-ebdaf83900fe" xlink:to="loc_ifrs-full_TreasurySharesMember_b2d50b77-b5ce-4e8d-9aee-7859ecbda12e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RetainedEarningsMember_9899ef1b-82a1-45fd-8082-537f783e8c0f" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EquityMember_fea92f26-797b-416f-ba36-ebdaf83900fe" xlink:to="loc_ifrs-full_RetainedEarningsMember_9899ef1b-82a1-45fd-8082-537f783e8c0f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ReserveOfSharebasedPaymentsMember_b7bc2a63-41c1-4fb5-95d5-2f7e1b310a37" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ReserveOfSharebasedPaymentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EquityMember_fea92f26-797b-416f-ba36-ebdaf83900fe" xlink:to="loc_ifrs-full_ReserveOfSharebasedPaymentsMember_b7bc2a63-41c1-4fb5-95d5-2f7e1b310a37" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AccumulatedOtherComprehensiveIncomeMember_8f541427-5407-45b0-8a9d-1f7359ff9d0f" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EquityMember_fea92f26-797b-416f-ba36-ebdaf83900fe" xlink:to="loc_ifrs-full_AccumulatedOtherComprehensiveIncomeMember_8f541427-5407-45b0-8a9d-1f7359ff9d0f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_EquityAttributableToOwnersOfParentMember_a3863123-e182-47c5-bdaa-e05c36807f2f" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_EquityAttributableToOwnersOfParentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EquityMember_fea92f26-797b-416f-ba36-ebdaf83900fe" xlink:to="loc_ifrs-full_EquityAttributableToOwnersOfParentMember_a3863123-e182-47c5-bdaa-e05c36807f2f" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_NoncontrollingInterestsMember_64d325d5-9c3b-494f-a30b-9f123a30577c" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncontrollingInterestsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EquityMember_fea92f26-797b-416f-ba36-ebdaf83900fe" xlink:to="loc_ifrs-full_NoncontrollingInterestsMember_64d325d5-9c3b-494f-a30b-9f123a30577c" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RetrospectiveApplicationAndRetrospectiveRestatementAxis_91eb1a11-051c-4fbf-ba10-b771dd62ea56" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RetrospectiveApplicationAndRetrospectiveRestatementAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_StatementOfChangesInEquityTable_d4a5f4e5-cf9d-4565-8475-d4ea0b292587" xlink:to="loc_ifrs-full_RetrospectiveApplicationAndRetrospectiveRestatementAxis_91eb1a11-051c-4fbf-ba10-b771dd62ea56" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RestatedMember_ff757409-de03-4609-85aa-cbc33b234794" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RestatedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_RetrospectiveApplicationAndRetrospectiveRestatementAxis_91eb1a11-051c-4fbf-ba10-b771dd62ea56" xlink:to="loc_ifrs-full_RestatedMember_ff757409-de03-4609-85aa-cbc33b234794" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_PreviouslyStatedMember_fcbe2dac-7e34-4b5b-9ac5-67e62ecfbc12" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PreviouslyStatedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_RestatedMember_ff757409-de03-4609-85aa-cbc33b234794" xlink:to="loc_ifrs-full_PreviouslyStatedMember_fcbe2dac-7e34-4b5b-9ac5-67e62ecfbc12" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_IncidenceDeLapplicationDeLaDecisionIfricSurIas19Member_1deae2bd-7a7f-4056-9a34-3058b1a901fd" xlink:href="sny-2021-12-31.xsd#sny_IncidenceDeLapplicationDeLaDecisionIfricSurIas19Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_RestatedMember_ff757409-de03-4609-85aa-cbc33b234794" xlink:to="loc_sny_IncidenceDeLapplicationDeLaDecisionIfricSurIas19Member_1deae2bd-7a7f-4056-9a34-3058b1a901fd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_IncidenceDeLapplicationDeLaDecisionIfricSurLesContratsDeTypeSaasMember_ca523b20-ec3a-42b1-8e75-aa3f630e6ae0" xlink:href="sny-2021-12-31.xsd#sny_IncidenceDeLapplicationDeLaDecisionIfricSurLesContratsDeTypeSaasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_RestatedMember_ff757409-de03-4609-85aa-cbc33b234794" xlink:to="loc_sny_IncidenceDeLapplicationDeLaDecisionIfricSurLesContratsDeTypeSaasMember_ca523b20-ec3a-42b1-8e75-aa3f630e6ae0" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.sanofi.com/role/tatdesfluxdetrsoreriemthodeindirecteDtails" xlink:type="simple" xlink:href="sny-2021-12-31.xsd#tatdesfluxdetrsoreriemthodeindirecteDtails"/>
  <link:definitionLink xlink:role="http://www.sanofi.com/role/tatdesfluxdetrsoreriemthodeindirecteDtails" xlink:type="extended" id="i9c4625d4d10649bfaf071c67a689e7f8_tatdesfluxdetrsoreriemthodeindirecteDtails">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfFairValueMeasurementOfAssetsLineItems_c90500b2-541b-4f1b-b900-80227e99aa6d" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DisclosureOfFairValueMeasurementOfAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncomeTaxesPaidRefundClassifiedAsOperatingActivities_88445cf4-3fc4-48dc-bc4e-833b84010552" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IncomeTaxesPaidRefundClassifiedAsOperatingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfFairValueMeasurementOfAssetsLineItems_c90500b2-541b-4f1b-b900-80227e99aa6d" xlink:to="loc_ifrs-full_IncomeTaxesPaidRefundClassifiedAsOperatingActivities_88445cf4-3fc4-48dc-bc4e-833b84010552" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_InterestPaidClassifiedAsOperatingActivities_90339ef0-c749-4eeb-b5f5-4cfb22e16624" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_InterestPaidClassifiedAsOperatingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfFairValueMeasurementOfAssetsLineItems_c90500b2-541b-4f1b-b900-80227e99aa6d" xlink:to="loc_ifrs-full_InterestPaidClassifiedAsOperatingActivities_90339ef0-c749-4eeb-b5f5-4cfb22e16624" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_InterestReceivedClassifiedAsOperatingActivities_3af5f981-da99-4aea-996b-fc746f828215" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_InterestReceivedClassifiedAsOperatingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfFairValueMeasurementOfAssetsLineItems_c90500b2-541b-4f1b-b900-80227e99aa6d" xlink:to="loc_ifrs-full_InterestReceivedClassifiedAsOperatingActivities_3af5f981-da99-4aea-996b-fc746f828215" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_DividendesRecusDesSocietesNonConsolideesClassesDansLesActivitesOperationnelles_d081055c-73cd-49f2-9691-db5d16b1e146" xlink:href="sny-2021-12-31.xsd#sny_DividendesRecusDesSocietesNonConsolideesClassesDansLesActivitesOperationnelles"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfFairValueMeasurementOfAssetsLineItems_c90500b2-541b-4f1b-b900-80227e99aa6d" xlink:to="loc_sny_DividendesRecusDesSocietesNonConsolideesClassesDansLesActivitesOperationnelles_d081055c-73cd-49f2-9691-db5d16b1e146" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProceedsFromDisposalsOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets_07178e1d-388e-417b-a769-441169aa2099" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProceedsFromDisposalsOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfFairValueMeasurementOfAssetsLineItems_c90500b2-541b-4f1b-b900-80227e99aa6d" xlink:to="loc_ifrs-full_ProceedsFromDisposalsOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets_07178e1d-388e-417b-a769-441169aa2099" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProceedsFromSalesOfInvestmentsAccountedForUsingEquityMethod_310b66d9-2003-4504-8805-846801e94eb9" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProceedsFromSalesOfInvestmentsAccountedForUsingEquityMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfFairValueMeasurementOfAssetsLineItems_c90500b2-541b-4f1b-b900-80227e99aa6d" xlink:to="loc_ifrs-full_ProceedsFromSalesOfInvestmentsAccountedForUsingEquityMethod_310b66d9-2003-4504-8805-846801e94eb9" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AjustementPourProfitsPertesRealisesSurLaCessionDeParticipationsDansDesFilialesDesCoentreprisesEtDesEntreprisesAssocieesImpotsDifferes_6b11f121-2596-4162-a1f0-7ae562c5868f" xlink:href="sny-2021-12-31.xsd#sny_AjustementPourProfitsPertesRealisesSurLaCessionDeParticipationsDansDesFilialesDesCoentreprisesEtDesEntreprisesAssocieesImpotsDifferes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfFairValueMeasurementOfAssetsLineItems_c90500b2-541b-4f1b-b900-80227e99aa6d" xlink:to="loc_sny_AjustementPourProfitsPertesRealisesSurLaCessionDeParticipationsDansDesFilialesDesCoentreprisesEtDesEntreprisesAssocieesImpotsDifferes_6b11f121-2596-4162-a1f0-7ae562c5868f" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfFairValueMeasurementOfAssetsTable_ef94be7d-d192-497f-8ccb-5404d23c0b32" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DisclosureOfFairValueMeasurementOfAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfFairValueMeasurementOfAssetsLineItems_c90500b2-541b-4f1b-b900-80227e99aa6d" xlink:to="loc_ifrs-full_DisclosureOfFairValueMeasurementOfAssetsTable_ef94be7d-d192-497f-8ccb-5404d23c0b32" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="scenario"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfAssetsAxis_2ae23de8-7351-429d-83ad-9226b6e17208" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ClassesOfAssetsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfFairValueMeasurementOfAssetsTable_ef94be7d-d192-497f-8ccb-5404d23c0b32" xlink:to="loc_ifrs-full_ClassesOfAssetsAxis_2ae23de8-7351-429d-83ad-9226b6e17208" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfAssetsMember_f3dd4ed2-5f87-49d7-a730-236bc6bb5e40" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ClassesOfAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ClassesOfAssetsAxis_2ae23de8-7351-429d-83ad-9226b6e17208" xlink:to="loc_ifrs-full_ClassesOfAssetsMember_f3dd4ed2-5f87-49d7-a730-236bc6bb5e40" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_ComplementDePrixSurCessionPasseeMember_aa82e9bb-324a-47d8-9d59-ead00a949d00" xlink:href="sny-2021-12-31.xsd#sny_ComplementDePrixSurCessionPasseeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfAssetsMember_f3dd4ed2-5f87-49d7-a730-236bc6bb5e40" xlink:to="loc_sny_ComplementDePrixSurCessionPasseeMember_aa82e9bb-324a-47d8-9d59-ead00a949d00" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_ParticipationsMember_3ce834b8-d27d-4500-a54e-ebf2295b186f" xlink:href="sny-2021-12-31.xsd#sny_ParticipationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfAssetsMember_f3dd4ed2-5f87-49d7-a730-236bc6bb5e40" xlink:to="loc_sny_ParticipationsMember_3ce834b8-d27d-4500-a54e-ebf2295b186f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_InvestmentsInEquityInstrumentsMeasuredAtFairValueThroughOtherComprehensiveIncomeAxis_d264cf62-f141-4195-94f1-d97a76f2400d" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_InvestmentsInEquityInstrumentsMeasuredAtFairValueThroughOtherComprehensiveIncomeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfFairValueMeasurementOfAssetsTable_ef94be7d-d192-497f-8ccb-5404d23c0b32" xlink:to="loc_ifrs-full_InvestmentsInEquityInstrumentsMeasuredAtFairValueThroughOtherComprehensiveIncomeAxis_d264cf62-f141-4195-94f1-d97a76f2400d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_InvestmentsInEquityInstrumentsMeasuredAtFairValueThroughOtherComprehensiveIncomeMember_6be3fdbd-4527-4d66-821d-98e0878a9f0c" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_InvestmentsInEquityInstrumentsMeasuredAtFairValueThroughOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_InvestmentsInEquityInstrumentsMeasuredAtFairValueThroughOtherComprehensiveIncomeAxis_d264cf62-f141-4195-94f1-d97a76f2400d" xlink:to="loc_ifrs-full_InvestmentsInEquityInstrumentsMeasuredAtFairValueThroughOtherComprehensiveIncomeMember_6be3fdbd-4527-4d66-821d-98e0878a9f0c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AlnylamPharmaceuticalsIncMember_f106c5f4-04f0-45f4-a67c-c3e78213de83" xlink:href="sny-2021-12-31.xsd#sny_AlnylamPharmaceuticalsIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_InvestmentsInEquityInstrumentsMeasuredAtFairValueThroughOtherComprehensiveIncomeMember_6be3fdbd-4527-4d66-821d-98e0878a9f0c" xlink:to="loc_sny_AlnylamPharmaceuticalsIncMember_f106c5f4-04f0-45f4-a67c-c3e78213de83" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_MyokardiaIncMember_097c4a71-781d-4ab5-adb4-94574fe25dac" xlink:href="sny-2021-12-31.xsd#sny_MyokardiaIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_InvestmentsInEquityInstrumentsMeasuredAtFairValueThroughOtherComprehensiveIncomeMember_6be3fdbd-4527-4d66-821d-98e0878a9f0c" xlink:to="loc_sny_MyokardiaIncMember_097c4a71-781d-4ab5-adb4-94574fe25dac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesAxis_ebc76510-d9d1-4dc9-a33d-e3e3f3ab0ecf" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProductsAndServicesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfFairValueMeasurementOfAssetsTable_ef94be7d-d192-497f-8ccb-5404d23c0b32" xlink:to="loc_ifrs-full_ProductsAndServicesAxis_ebc76510-d9d1-4dc9-a33d-e3e3f3ab0ecf" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesMember_d2a1d50a-a729-4279-b7a1-1bd0fd0ad8aa" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProductsAndServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_ebc76510-d9d1-4dc9-a33d-e3e3f3ab0ecf" xlink:to="loc_ifrs-full_ProductsAndServicesMember_d2a1d50a-a729-4279-b7a1-1bd0fd0ad8aa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_PrescriptionMember_f637e5f6-f897-4da2-a929-a26ec32075ae" xlink:href="sny-2021-12-31.xsd#sny_PrescriptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesMember_d2a1d50a-a729-4279-b7a1-1bd0fd0ad8aa" xlink:to="loc_sny_PrescriptionMember_f637e5f6-f897-4da2-a929-a26ec32075ae" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_SanteGrandPublicMember_19db7544-79c0-4f75-9ede-ef0022f49e96" xlink:href="sny-2021-12-31.xsd#sny_SanteGrandPublicMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesMember_d2a1d50a-a729-4279-b7a1-1bd0fd0ad8aa" xlink:to="loc_sny_SanteGrandPublicMember_19db7544-79c0-4f75-9ede-ef0022f49e96" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_SeprafilmMember_46ab5525-f160-4bda-9619-7ba185954e70" xlink:href="sny-2021-12-31.xsd#sny_SeprafilmMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesMember_d2a1d50a-a729-4279-b7a1-1bd0fd0ad8aa" xlink:to="loc_sny_SeprafilmMember_46ab5525-f160-4bda-9619-7ba185954e70" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_SignificantInvestmentsInAssociatesAxis_df973295-8dfb-4517-b5bb-dd15a7847cda" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_SignificantInvestmentsInAssociatesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfFairValueMeasurementOfAssetsTable_ef94be7d-d192-497f-8ccb-5404d23c0b32" xlink:to="loc_ifrs-full_SignificantInvestmentsInAssociatesAxis_df973295-8dfb-4517-b5bb-dd15a7847cda" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_EntitysTotalForAssociatesMember_7b44bf12-b59d-4c06-89ea-eb9b2d6de287" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_EntitysTotalForAssociatesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_SignificantInvestmentsInAssociatesAxis_df973295-8dfb-4517-b5bb-dd15a7847cda" xlink:to="loc_ifrs-full_EntitysTotalForAssociatesMember_7b44bf12-b59d-4c06-89ea-eb9b2d6de287" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_RegeneronMember_a015cd56-8da3-4966-9e44-6e57ae91932a" xlink:href="sny-2021-12-31.xsd#sny_RegeneronMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForAssociatesMember_7b44bf12-b59d-4c06-89ea-eb9b2d6de287" xlink:to="loc_sny_RegeneronMember_a015cd56-8da3-4966-9e44-6e57ae91932a" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.esma.europa.eu/xbrl/role/cor/esef_role-999999" xlink:type="simple" xlink:href="http://www.esma.europa.eu/taxonomy/2020-03-16/esef_cor.xsd#esef_role-999999"/>
  <link:definitionLink xlink:role="http://www.esma.europa.eu/xbrl/role/cor/esef_role-999999" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:href="http://www.esma.europa.eu/taxonomy/2020-03-16/esef_cor.xsd#esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_NameOfReportingEntityOrOtherMeansOfIdentification_6fe17eea-a6da-43a5-b4d6-9185f4b99df1NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NameOfReportingEntityOrOtherMeansOfIdentification"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_NameOfReportingEntityOrOtherMeansOfIdentification_6fe17eea-a6da-43a5-b4d6-9185f4b99df1NotDimensionallyQualified" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ExplanationOfChangeInNameOfReportingEntityOrOtherMeansOfIdentificationFromEndOfPrecedingReportingPeriod_bdfebfdc-b59a-47fe-9b58-56ce2855805aNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ExplanationOfChangeInNameOfReportingEntityOrOtherMeansOfIdentificationFromEndOfPrecedingReportingPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ExplanationOfChangeInNameOfReportingEntityOrOtherMeansOfIdentificationFromEndOfPrecedingReportingPeriod_bdfebfdc-b59a-47fe-9b58-56ce2855805aNotDimensionallyQualified" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_NameOfParentEntity_1cbd594c-b166-4233-84e8-0522334b701dNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NameOfParentEntity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_NameOfParentEntity_1cbd594c-b166-4233-84e8-0522334b701dNotDimensionallyQualified" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_NameOfUltimateParentOfGroup_fa6e63cf-f4f5-403b-86e9-4bafe85508cbNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NameOfUltimateParentOfGroup"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_NameOfUltimateParentOfGroup_fa6e63cf-f4f5-403b-86e9-4bafe85508cbNotDimensionallyQualified" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AddressOfRegisteredOfficeOfEntity_30be4f99-415d-4b0c-93e9-31d963e6f828NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AddressOfRegisteredOfficeOfEntity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_AddressOfRegisteredOfficeOfEntity_30be4f99-415d-4b0c-93e9-31d963e6f828NotDimensionallyQualified" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DomicileOfEntity_ad23582d-3702-4efe-b988-d7cc9fa7bea6NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DomicileOfEntity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_DomicileOfEntity_ad23582d-3702-4efe-b988-d7cc9fa7bea6NotDimensionallyQualified" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CountryOfIncorporation_e63b6d9b-b434-4fdb-ba3c-cdc3985dd6abNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CountryOfIncorporation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CountryOfIncorporation_e63b6d9b-b434-4fdb-ba3c-cdc3985dd6abNotDimensionallyQualified" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_LegalFormOfEntity_70c9251f-3e12-4cab-8e86-b93e9eb79d11NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_LegalFormOfEntity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_LegalFormOfEntity_70c9251f-3e12-4cab-8e86-b93e9eb79d11NotDimensionallyQualified" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DescriptionOfNatureOfEntitysOperationsAndPrincipalActivities_1087f889-45e5-441c-af80-a664a806cf59NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DescriptionOfNatureOfEntitysOperationsAndPrincipalActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_DescriptionOfNatureOfEntitysOperationsAndPrincipalActivities_1087f889-45e5-441c-af80-a664a806cf59NotDimensionallyQualified" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_PrincipalPlaceOfBusiness_12fee39b-737c-4ef6-8720-8e0261f9199bNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PrincipalPlaceOfBusiness"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_PrincipalPlaceOfBusiness_12fee39b-737c-4ef6-8720-8e0261f9199bNotDimensionallyQualified" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_PropertyPlantAndEquipment_28dce3f1-e36a-4fcc-b4b2-129d5d04b92aNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_PropertyPlantAndEquipment_28dce3f1-e36a-4fcc-b4b2-129d5d04b92aNotDimensionallyQualified" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RightofuseAssets_9b248483-0b69-40e1-96ca-b4829149edf2NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RightofuseAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_RightofuseAssets_9b248483-0b69-40e1-96ca-b4829149edf2NotDimensionallyQualified" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Goodwill_4a327a59-8166-4b59-9e2c-972b7039d07bNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_Goodwill_4a327a59-8166-4b59-9e2c-972b7039d07bNotDimensionallyQualified" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IntangibleAssetsOtherThanGoodwill_c197ba1d-9765-4e98-83d6-032ac302b298NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IntangibleAssetsOtherThanGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_IntangibleAssetsOtherThanGoodwill_c197ba1d-9765-4e98-83d6-032ac302b298NotDimensionallyQualified" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_InvestmentAccountedForUsingEquityMethod_0cabd361-b972-4c1f-a11c-0cb9648d6cbaNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_InvestmentAccountedForUsingEquityMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_InvestmentAccountedForUsingEquityMethod_0cabd361-b972-4c1f-a11c-0cb9648d6cbaNotDimensionallyQualified" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherNoncurrentAssets_1ded936d-94fd-4f1e-b3fc-5bd4ee149742NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherNoncurrentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_OtherNoncurrentAssets_1ded936d-94fd-4f1e-b3fc-5bd4ee149742NotDimensionallyQualified" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CurrentTaxAssetsNoncurrent_995b78e1-25bc-4635-8efd-a9ba516201c5NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentTaxAssetsNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CurrentTaxAssetsNoncurrent_995b78e1-25bc-4635-8efd-a9ba516201c5NotDimensionallyQualified" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DeferredTaxAssets_357138f9-1c6a-4336-bb56-87a7e3e6daaeNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DeferredTaxAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_DeferredTaxAssets_357138f9-1c6a-4336-bb56-87a7e3e6daaeNotDimensionallyQualified" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_NoncurrentAssets_cf5cc3c6-b3fe-4b70-b462-cdda62bb71ecNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_NoncurrentAssets_cf5cc3c6-b3fe-4b70-b462-cdda62bb71ecNotDimensionallyQualified" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Inventories_71ef21dc-c357-4c74-9c37-df1e834d3c8eNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_Inventories"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_Inventories_71ef21dc-c357-4c74-9c37-df1e834d3c8eNotDimensionallyQualified" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CurrentTradeReceivables_f60af388-094e-4e02-8556-fcbb0d3adb4aNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentTradeReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CurrentTradeReceivables_f60af388-094e-4e02-8556-fcbb0d3adb4aNotDimensionallyQualified" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherCurrentAssets_8f3a00ee-00f0-4759-ab1c-293b51565249NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherCurrentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_OtherCurrentAssets_8f3a00ee-00f0-4759-ab1c-293b51565249NotDimensionallyQualified" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CurrentTaxAssetsCurrent_47394e50-c832-4cad-8141-0b55b6426f2fNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentTaxAssetsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CurrentTaxAssetsCurrent_47394e50-c832-4cad-8141-0b55b6426f2fNotDimensionallyQualified" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CashAndCashEquivalents_6113b00b-5f79-4196-8135-f5cb98c0b3a0NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashAndCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CashAndCashEquivalents_6113b00b-5f79-4196-8135-f5cb98c0b3a0NotDimensionallyQualified" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CurrentAssetsOtherThanAssetsOrDisposalGroupsClassifiedAsHeldForSaleOrAsHeldForDistributionToOwners_2992d178-b01d-499e-bdc5-cd920fee67f1NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentAssetsOtherThanAssetsOrDisposalGroupsClassifiedAsHeldForSaleOrAsHeldForDistributionToOwners"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CurrentAssetsOtherThanAssetsOrDisposalGroupsClassifiedAsHeldForSaleOrAsHeldForDistributionToOwners_2992d178-b01d-499e-bdc5-cd920fee67f1NotDimensionallyQualified" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_NoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSale_792edee3-9f0c-4a1d-ac1a-33cdc1535619NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSale"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_NoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSale_792edee3-9f0c-4a1d-ac1a-33cdc1535619NotDimensionallyQualified" xlink:type="arc" order="25"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Assets_68e70c6c-0fd8-4599-b3c3-4452d0783d69NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_Assets_68e70c6c-0fd8-4599-b3c3-4452d0783d69NotDimensionallyQualified" xlink:type="arc" order="26"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_EquityAttributableToOwnersOfParent_e195ff12-969c-447c-8cfb-be42764af5d3NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_EquityAttributableToOwnersOfParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_EquityAttributableToOwnersOfParent_e195ff12-969c-447c-8cfb-be42764af5d3NotDimensionallyQualified" xlink:type="arc" order="27"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_NoncontrollingInterests_66ef509d-b153-49fa-aaff-fb95f525fb4aNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncontrollingInterests"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_NoncontrollingInterests_66ef509d-b153-49fa-aaff-fb95f525fb4aNotDimensionallyQualified" xlink:type="arc" order="28"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Equity_33d10d43-a1ed-43d4-93e3-add4c901c8c7NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_Equity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_Equity_33d10d43-a1ed-43d4-93e3-add4c901c8c7NotDimensionallyQualified" xlink:type="arc" order="29"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_LongtermBorrowings_7c0470bd-6d76-48fc-90c2-5992bd37a1fdNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_LongtermBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_LongtermBorrowings_7c0470bd-6d76-48fc-90c2-5992bd37a1fdNotDimensionallyQualified" xlink:type="arc" order="30"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_NoncurrentLeaseLiabilities_db53b58d-5379-4130-8bc1-0622211435f9NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentLeaseLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_NoncurrentLeaseLiabilities_db53b58d-5379-4130-8bc1-0622211435f9NotDimensionallyQualified" xlink:type="arc" order="31"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_PassifsNonCourantsLiesADesRegroupementsDentreprisesEtADesInteretsNonControlants_1338bc23-a70d-417a-be8e-9ca897b23e66NotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_PassifsNonCourantsLiesADesRegroupementsDentreprisesEtADesInteretsNonControlants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_PassifsNonCourantsLiesADesRegroupementsDentreprisesEtADesInteretsNonControlants_1338bc23-a70d-417a-be8e-9ca897b23e66NotDimensionallyQualified" xlink:type="arc" order="32"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_ProvisionsEtAutresPassifsNonCourants_0266fed3-014d-40ca-a6ee-abe0f68ae706NotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_ProvisionsEtAutresPassifsNonCourants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_ProvisionsEtAutresPassifsNonCourants_0266fed3-014d-40ca-a6ee-abe0f68ae706NotDimensionallyQualified" xlink:type="arc" order="33"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CurrentTaxLiabilitiesNoncurrent_056cafe1-a19c-4c84-8737-9c657a5a0ea8NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentTaxLiabilitiesNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CurrentTaxLiabilitiesNoncurrent_056cafe1-a19c-4c84-8737-9c657a5a0ea8NotDimensionallyQualified" xlink:type="arc" order="34"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DeferredTaxLiabilities_77303201-e757-4bcc-b096-735d561b87a2NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DeferredTaxLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_DeferredTaxLiabilities_77303201-e757-4bcc-b096-735d561b87a2NotDimensionallyQualified" xlink:type="arc" order="35"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_NoncurrentLiabilities_9261b898-2ecd-4174-b5b4-258623b5d0d5NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_NoncurrentLiabilities_9261b898-2ecd-4174-b5b4-258623b5d0d5NotDimensionallyQualified" xlink:type="arc" order="36"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_TradeAndOtherCurrentPayablesToTradeSuppliers_dbe19bb5-07de-41ac-80a4-0860becd3bafNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_TradeAndOtherCurrentPayablesToTradeSuppliers"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_TradeAndOtherCurrentPayablesToTradeSuppliers_dbe19bb5-07de-41ac-80a4-0860becd3bafNotDimensionallyQualified" xlink:type="arc" order="37"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_PassifsCourantsLiesADesRegroupementsDentreprisesEtADesInteretsNonControlants_6d119995-f2ca-4ffe-b93f-358603de21b9NotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_PassifsCourantsLiesADesRegroupementsDentreprisesEtADesInteretsNonControlants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_PassifsCourantsLiesADesRegroupementsDentreprisesEtADesInteretsNonControlants_6d119995-f2ca-4ffe-b93f-358603de21b9NotDimensionallyQualified" xlink:type="arc" order="38"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_ProvisionsEtAutresPassifsCourants_2ce0b5b7-30c0-4f8e-b1be-a263036d7859NotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_ProvisionsEtAutresPassifsCourants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_ProvisionsEtAutresPassifsCourants_2ce0b5b7-30c0-4f8e-b1be-a263036d7859NotDimensionallyQualified" xlink:type="arc" order="39"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CurrentTaxLiabilitiesCurrent_21f87dc7-8b69-4bba-bd92-548a17e7c194NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentTaxLiabilitiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CurrentTaxLiabilitiesCurrent_21f87dc7-8b69-4bba-bd92-548a17e7c194NotDimensionallyQualified" xlink:type="arc" order="40"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CurrentLeaseLiabilities_983967fa-e8e3-48d7-a488-971febb7f3ffNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentLeaseLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CurrentLeaseLiabilities_983967fa-e8e3-48d7-a488-971febb7f3ffNotDimensionallyQualified" xlink:type="arc" order="41"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CurrentBorrowingsAndCurrentPortionOfNoncurrentBorrowings_04635940-2e3b-4937-860a-11dbbb749f62NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentBorrowingsAndCurrentPortionOfNoncurrentBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CurrentBorrowingsAndCurrentPortionOfNoncurrentBorrowings_04635940-2e3b-4937-860a-11dbbb749f62NotDimensionallyQualified" xlink:type="arc" order="42"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CurrentLiabilitiesOtherThanLiabilitiesIncludedInDisposalGroupsClassifiedAsHeldForSale_a47a2c18-e299-4753-b6a9-87b084b2c884NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentLiabilitiesOtherThanLiabilitiesIncludedInDisposalGroupsClassifiedAsHeldForSale"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CurrentLiabilitiesOtherThanLiabilitiesIncludedInDisposalGroupsClassifiedAsHeldForSale_a47a2c18-e299-4753-b6a9-87b084b2c884NotDimensionallyQualified" xlink:type="arc" order="43"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_LiabilitiesIncludedInDisposalGroupsClassifiedAsHeldForSale_9b2054c0-843f-44d1-a7b4-d2ca93e24794NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_LiabilitiesIncludedInDisposalGroupsClassifiedAsHeldForSale"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_LiabilitiesIncludedInDisposalGroupsClassifiedAsHeldForSale_9b2054c0-843f-44d1-a7b4-d2ca93e24794NotDimensionallyQualified" xlink:type="arc" order="44"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_EquityAndLiabilities_5536a264-8a48-42b6-89eb-98864931f470NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_EquityAndLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_EquityAndLiabilities_5536a264-8a48-42b6-89eb-98864931f470NotDimensionallyQualified" xlink:type="arc" order="45"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RevenueFromSaleOfGoods_752d1374-1192-4e7b-a0e1-8ad88d8255f0NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RevenueFromSaleOfGoods"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_RevenueFromSaleOfGoods_752d1374-1192-4e7b-a0e1-8ad88d8255f0NotDimensionallyQualified" xlink:type="arc" order="46"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherRevenue_34891596-98d6-499b-a571-f75751f4ae47NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_OtherRevenue_34891596-98d6-499b-a571-f75751f4ae47NotDimensionallyQualified" xlink:type="arc" order="47"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CostOfSales_244b41a6-0ab8-47b9-ac3a-2f62245d2881NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CostOfSales"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CostOfSales_244b41a6-0ab8-47b9-ac3a-2f62245d2881NotDimensionallyQualified" xlink:type="arc" order="48"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_GrossProfit_6d9511bd-5900-4b9d-9e49-aabe98689891NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_GrossProfit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_GrossProfit_6d9511bd-5900-4b9d-9e49-aabe98689891NotDimensionallyQualified" xlink:type="arc" order="49"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ResearchAndDevelopmentExpense_4db8bff7-af03-432b-ae3d-fe22550c508cNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ResearchAndDevelopmentExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ResearchAndDevelopmentExpense_4db8bff7-af03-432b-ae3d-fe22550c508cNotDimensionallyQualified" xlink:type="arc" order="50"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_SellingGeneralAndAdministrativeExpense_3a64d257-a915-4910-af5b-33e9aa31a689NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_SellingGeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_SellingGeneralAndAdministrativeExpense_3a64d257-a915-4910-af5b-33e9aa31a689NotDimensionallyQualified" xlink:type="arc" order="51"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_MiscellaneousOtherOperatingIncome_7960403b-4f25-43d0-bceb-84e8267a1e0bNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_MiscellaneousOtherOperatingIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_MiscellaneousOtherOperatingIncome_7960403b-4f25-43d0-bceb-84e8267a1e0bNotDimensionallyQualified" xlink:type="arc" order="52"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_MiscellaneousOtherOperatingExpense_0262c174-8a0c-4e1e-9ee1-0a32776bea8cNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_MiscellaneousOtherOperatingExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_MiscellaneousOtherOperatingExpense_0262c174-8a0c-4e1e-9ee1-0a32776bea8cNotDimensionallyQualified" xlink:type="arc" order="53"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AmortisationIntangibleAssetsOtherThanGoodwill_6182d73e-dbf5-4ee4-96b6-77aaa80c1430NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AmortisationIntangibleAssetsOtherThanGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_AmortisationIntangibleAssetsOtherThanGoodwill_6182d73e-dbf5-4ee4-96b6-77aaa80c1430NotDimensionallyQualified" xlink:type="arc" order="54"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ImpairmentLossRecognisedInProfitOrLossIntangibleAssetsOtherThanGoodwill_10a5a7d1-2a9b-4b4c-960b-56d251bf814cNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ImpairmentLossRecognisedInProfitOrLossIntangibleAssetsOtherThanGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ImpairmentLossRecognisedInProfitOrLossIntangibleAssetsOtherThanGoodwill_10a5a7d1-2a9b-4b4c-960b-56d251bf814cNotDimensionallyQualified" xlink:type="arc" order="55"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncreaseDecreaseInContingentConsiderationAssetLiability_57e62066-f10f-49ca-9b6e-dd289daa2276NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IncreaseDecreaseInContingentConsiderationAssetLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_IncreaseDecreaseInContingentConsiderationAssetLiability_57e62066-f10f-49ca-9b6e-dd289daa2276NotDimensionallyQualified" xlink:type="arc" order="56"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ExpenseOfRestructuringActivities_37c01162-c007-4fc3-b9b7-86867d1ce8f6NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ExpenseOfRestructuringActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ExpenseOfRestructuringActivities_37c01162-c007-4fc3-b9b7-86867d1ce8f6NotDimensionallyQualified" xlink:type="arc" order="57"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AutresProfitsPertesLitiges_6f3b9baa-1f4a-4195-999b-15d544c66522NotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_AutresProfitsPertesLitiges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_AutresProfitsPertesLitiges_6f3b9baa-1f4a-4195-999b-15d544c66522NotDimensionallyQualified" xlink:type="arc" order="58"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_GainsOnDisposalsOfInvestments_3d0bbbe6-1a15-4e2b-9bf6-42895bdecf0fNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_GainsOnDisposalsOfInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_GainsOnDisposalsOfInvestments_3d0bbbe6-1a15-4e2b-9bf6-42895bdecf0fNotDimensionallyQualified" xlink:type="arc" order="59"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProfitLossFromOperatingActivities_13522460-f77d-4ebe-89b8-02358e96f2a7NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLossFromOperatingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ProfitLossFromOperatingActivities_13522460-f77d-4ebe-89b8-02358e96f2a7NotDimensionallyQualified" xlink:type="arc" order="60"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_FinanceCosts_41e090a7-2eca-4efe-a063-fef2dc544a80NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_FinanceCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_FinanceCosts_41e090a7-2eca-4efe-a063-fef2dc544a80NotDimensionallyQualified" xlink:type="arc" order="61"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_FinanceIncome_81882c46-58be-4e02-adee-4ee3d33bd132NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_FinanceIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_FinanceIncome_81882c46-58be-4e02-adee-4ee3d33bd132NotDimensionallyQualified" xlink:type="arc" order="62"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_ResultatAvantImpotsEtSocietesMisesEnEquivalence_b72279fa-06b9-4528-978b-feb3a01e9f27NotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_ResultatAvantImpotsEtSocietesMisesEnEquivalence"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_ResultatAvantImpotsEtSocietesMisesEnEquivalence_b72279fa-06b9-4528-978b-feb3a01e9f27NotDimensionallyQualified" xlink:type="arc" order="63"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncomeTaxExpenseContinuingOperations_6d4e697e-3440-46f7-b519-df2a157f07ddNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IncomeTaxExpenseContinuingOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_IncomeTaxExpenseContinuingOperations_6d4e697e-3440-46f7-b519-df2a157f07ddNotDimensionallyQualified" xlink:type="arc" order="64"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ShareOfProfitLossOfAssociatesAccountedForUsingEquityMethod_6616bd73-becc-44eb-baa7-11fe14f2b781NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ShareOfProfitLossOfAssociatesAccountedForUsingEquityMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ShareOfProfitLossOfAssociatesAccountedForUsingEquityMethod_6616bd73-becc-44eb-baa7-11fe14f2b781NotDimensionallyQualified" xlink:type="arc" order="65"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProfitLossFromContinuingOperations_7ae9f79d-0fd3-4fbe-933c-e7beb5b12188NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLossFromContinuingOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ProfitLossFromContinuingOperations_7ae9f79d-0fd3-4fbe-933c-e7beb5b12188NotDimensionallyQualified" xlink:type="arc" order="66"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProfitLossFromDiscontinuedOperations_2d7d2d56-40a4-4d65-8692-25ec409b0367NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLossFromDiscontinuedOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ProfitLossFromDiscontinuedOperations_2d7d2d56-40a4-4d65-8692-25ec409b0367NotDimensionallyQualified" xlink:type="arc" order="67"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProfitLoss_94441e17-064a-4ea9-ac91-0b4feabad0e0NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ProfitLoss_94441e17-064a-4ea9-ac91-0b4feabad0e0NotDimensionallyQualified" xlink:type="arc" order="68"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProfitLossAttributableToNoncontrollingInterests_61ea3fc8-ee6e-4736-8ace-b700786d0eeaNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLossAttributableToNoncontrollingInterests"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ProfitLossAttributableToNoncontrollingInterests_61ea3fc8-ee6e-4736-8ace-b700786d0eeaNotDimensionallyQualified" xlink:type="arc" order="69"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProfitLossAttributableToOwnersOfParent_22dcecf2-9e0b-4ff1-9aeb-e6a29e54d898NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLossAttributableToOwnersOfParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ProfitLossAttributableToOwnersOfParent_22dcecf2-9e0b-4ff1-9aeb-e6a29e54d898NotDimensionallyQualified" xlink:type="arc" order="70"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_WeightedAverageShares_4ba022e1-92f9-42d5-b06b-2f9dcab86162NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_WeightedAverageShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_WeightedAverageShares_4ba022e1-92f9-42d5-b06b-2f9dcab86162NotDimensionallyQualified" xlink:type="arc" order="71"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AdjustedWeightedAverageShares_365c4a32-f218-413d-86f8-8b7a402302b0NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustedWeightedAverageShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_AdjustedWeightedAverageShares_365c4a32-f218-413d-86f8-8b7a402302b0NotDimensionallyQualified" xlink:type="arc" order="72"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_ResultatDeBaseParActionAttribuableAuxActionnairesDeSanofi_cf60a402-8bbf-4d02-93b9-cccc68eb501aNotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_ResultatDeBaseParActionAttribuableAuxActionnairesDeSanofi"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_ResultatDeBaseParActionAttribuableAuxActionnairesDeSanofi_cf60a402-8bbf-4d02-93b9-cccc68eb501aNotDimensionallyQualified" xlink:type="arc" order="73"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_BasicEarningsLossPerShareFromContinuingOperations_49818ea1-ac42-4a09-99db-8b0e1f283218NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_BasicEarningsLossPerShareFromContinuingOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_BasicEarningsLossPerShareFromContinuingOperations_49818ea1-ac42-4a09-99db-8b0e1f283218NotDimensionallyQualified" xlink:type="arc" order="74"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_ResultatDilueParActionAttribuableAuxActionnairesDeSanofi_a1cc0ad8-0240-4cd1-b5a5-6a4821a55e36NotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_ResultatDilueParActionAttribuableAuxActionnairesDeSanofi"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_ResultatDilueParActionAttribuableAuxActionnairesDeSanofi_a1cc0ad8-0240-4cd1-b5a5-6a4821a55e36NotDimensionallyQualified" xlink:type="arc" order="75"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DilutedEarningsLossPerShareFromContinuingOperations_cf5ce3af-14d7-412c-a2ff-e0be88a196d4NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DilutedEarningsLossPerShareFromContinuingOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_DilutedEarningsLossPerShareFromContinuingOperations_cf5ce3af-14d7-412c-a2ff-e0be88a196d4NotDimensionallyQualified" xlink:type="arc" order="76"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ActuarialGainsLossesArisingFromChangesInFinancialAssumptionsNetDefinedBenefitLiabilityAsset_3a5f5882-26d1-4e28-9c44-759a04ccf62aNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ActuarialGainsLossesArisingFromChangesInFinancialAssumptionsNetDefinedBenefitLiabilityAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ActuarialGainsLossesArisingFromChangesInFinancialAssumptionsNetDefinedBenefitLiabilityAsset_3a5f5882-26d1-4e28-9c44-759a04ccf62aNotDimensionallyQualified" xlink:type="arc" order="77"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_GainsLossesRecognisedInOtherComprehensiveIncomeFairValueMeasurementEntitysOwnEquityInstruments_a4a8076a-6726-4eda-9517-b9d6a7b6e767NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_GainsLossesRecognisedInOtherComprehensiveIncomeFairValueMeasurementEntitysOwnEquityInstruments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_GainsLossesRecognisedInOtherComprehensiveIncomeFairValueMeasurementEntitysOwnEquityInstruments_a4a8076a-6726-4eda-9517-b9d6a7b6e767NotDimensionallyQualified" xlink:type="arc" order="78"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncomeTaxRelatingToComponentsOfOtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLoss_dd24cfe7-948a-4301-820b-a5e76b6ccffdNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IncomeTaxRelatingToComponentsOfOtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_IncomeTaxRelatingToComponentsOfOtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLoss_dd24cfe7-948a-4301-820b-a5e76b6ccffdNotDimensionallyQualified" xlink:type="arc" order="79"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossNetOfTax_564731bf-8552-4435-8647-9d0693d5fac4NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_OtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossNetOfTax_564731bf-8552-4435-8647-9d0693d5fac4NotDimensionallyQualified" xlink:type="arc" order="80"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_ProfitsPertesSurInstrumentsDeDetteEnActifsFinanciersAvantImpot_57d0229a-2d08-4944-866b-b79630bbbd73NotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_ProfitsPertesSurInstrumentsDeDetteEnActifsFinanciersAvantImpot"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_ProfitsPertesSurInstrumentsDeDetteEnActifsFinanciersAvantImpot_57d0229a-2d08-4944-866b-b79630bbbd73NotDimensionallyQualified" xlink:type="arc" order="81"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_GainsLossesOnCashFlowHedgesBeforeTax_169df435-1c1a-45b3-a5f0-35b4fd5b71f7NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_GainsLossesOnCashFlowHedgesBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_GainsLossesOnCashFlowHedgesBeforeTax_169df435-1c1a-45b3-a5f0-35b4fd5b71f7NotDimensionallyQualified" xlink:type="arc" order="82"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_GainsLossesOnExchangeDifferencesOnTranslationBeforeTax_f1a98620-6456-4da1-bd73-30597afbe5b9NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_GainsLossesOnExchangeDifferencesOnTranslationBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_GainsLossesOnExchangeDifferencesOnTranslationBeforeTax_f1a98620-6456-4da1-bd73-30597afbe5b9NotDimensionallyQualified" xlink:type="arc" order="83"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncomeTaxRelatingToComponentsOfOtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLoss_10683ede-2a64-40b6-a362-6f53da1f1d52NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IncomeTaxRelatingToComponentsOfOtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_IncomeTaxRelatingToComponentsOfOtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLoss_10683ede-2a64-40b6-a362-6f53da1f1d52NotDimensionallyQualified" xlink:type="arc" order="84"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLossNetOfTax_2f472aa2-a581-413b-ac16-47f253aeaa2fNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_OtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLossNetOfTax_2f472aa2-a581-413b-ac16-47f253aeaa2fNotDimensionallyQualified" xlink:type="arc" order="85"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherComprehensiveIncome_bfa6130a-8941-4f4a-b41e-00453305d97aNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherComprehensiveIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_OtherComprehensiveIncome_bfa6130a-8941-4f4a-b41e-00453305d97aNotDimensionallyQualified" xlink:type="arc" order="86"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ComprehensiveIncome_a032b67d-0f0d-410f-81f1-7ab780c6246fNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ComprehensiveIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ComprehensiveIncome_a032b67d-0f0d-410f-81f1-7ab780c6246fNotDimensionallyQualified" xlink:type="arc" order="87"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ComprehensiveIncomeAttributableToOwnersOfParent_a1e44672-f7af-4d0f-9616-d27d27df8f76NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ComprehensiveIncomeAttributableToOwnersOfParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ComprehensiveIncomeAttributableToOwnersOfParent_a1e44672-f7af-4d0f-9616-d27d27df8f76NotDimensionallyQualified" xlink:type="arc" order="88"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ComprehensiveIncomeAttributableToNoncontrollingInterests_54deac5b-218a-4186-947e-74a1f58dc5e6NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ComprehensiveIncomeAttributableToNoncontrollingInterests"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ComprehensiveIncomeAttributableToNoncontrollingInterests_54deac5b-218a-4186-947e-74a1f58dc5e6NotDimensionallyQualified" xlink:type="arc" order="89"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DividendsPaidOrdinarySharesPerShare_b7e6a6da-2ca0-4563-b64a-15f1e75a0395NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DividendsPaidOrdinarySharesPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_DividendsPaidOrdinarySharesPerShare_b7e6a6da-2ca0-4563-b64a-15f1e75a0395NotDimensionallyQualified" xlink:type="arc" order="90"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProfitLossAttributableToOrdinaryEquityHoldersOfParentEntity_2d828d02-1768-45a1-92ba-9a5d5cb2ddd0NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLossAttributableToOrdinaryEquityHoldersOfParentEntity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ProfitLossAttributableToOrdinaryEquityHoldersOfParentEntity_2d828d02-1768-45a1-92ba-9a5d5cb2ddd0NotDimensionallyQualified" xlink:type="arc" order="91"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AdjustmentsForUndistributedProfitsOfInvestmentsAccountedForUsingEquityMethod_fd860299-e5b2-43e5-a60d-c2a375655c8fNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForUndistributedProfitsOfInvestmentsAccountedForUsingEquityMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_AdjustmentsForUndistributedProfitsOfInvestmentsAccountedForUsingEquityMethod_fd860299-e5b2-43e5-a60d-c2a375655c8fNotDimensionallyQualified" xlink:type="arc" order="92"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AjustementsPourAmortissementsEtDepreciationsDesImmobilisationsCorporellesDroitsDutilisationEtImmobilisationsIncorporelles_d2bec44e-4642-4a00-a0ea-5a1cd3873794NotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_AjustementsPourAmortissementsEtDepreciationsDesImmobilisationsCorporellesDroitsDutilisationEtImmobilisationsIncorporelles"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_AjustementsPourAmortissementsEtDepreciationsDesImmobilisationsCorporellesDroitsDutilisationEtImmobilisationsIncorporelles_d2bec44e-4642-4a00-a0ea-5a1cd3873794NotDimensionallyQualified" xlink:type="arc" order="93"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AdjustmentsForLossesGainsOnDisposalOfNoncurrentAssets_2638c1ec-3812-43aa-a0e2-87ac3b587f79NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForLossesGainsOnDisposalOfNoncurrentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_AdjustmentsForLossesGainsOnDisposalOfNoncurrentAssets_2638c1ec-3812-43aa-a0e2-87ac3b587f79NotDimensionallyQualified" xlink:type="arc" order="94"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AdjustmentsForGainLossOnDisposalOfInvestmentsInSubsidiariesJointVenturesAndAssociates_9dabddc8-31aa-415c-bbe1-1b083f3f13fcNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForGainLossOnDisposalOfInvestmentsInSubsidiariesJointVenturesAndAssociates"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_AdjustmentsForGainLossOnDisposalOfInvestmentsInSubsidiariesJointVenturesAndAssociates_9dabddc8-31aa-415c-bbe1-1b083f3f13fcNotDimensionallyQualified" xlink:type="arc" order="95"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AdjustmentsForDeferredTaxExpense_8728bd08-4dc2-4276-8ceb-9c3725b58846NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForDeferredTaxExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_AdjustmentsForDeferredTaxExpense_8728bd08-4dc2-4276-8ceb-9c3725b58846NotDimensionallyQualified" xlink:type="arc" order="96"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AjustementsPourVariationDesProvisionsEtAutresPassifsNonCourants_fe5d6295-380e-4c13-96a6-2bcde2385190NotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_AjustementsPourVariationDesProvisionsEtAutresPassifsNonCourants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_AjustementsPourVariationDesProvisionsEtAutresPassifsNonCourants_fe5d6295-380e-4c13-96a6-2bcde2385190NotDimensionallyQualified" xlink:type="arc" order="97"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AdjustmentsForSharebasedPayments_b5f4e73f-f47d-45c7-aa1f-b194c57c494bNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForSharebasedPayments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_AdjustmentsForSharebasedPayments_b5f4e73f-f47d-45c7-aa1f-b194c57c494bNotDimensionallyQualified" xlink:type="arc" order="98"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AjustementsPourImpactDeLaConsommationDesStocksAcquisReevaluesALaJusteValeur_000b1061-e7b7-46fa-8e89-f891623d3dedNotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_AjustementsPourImpactDeLaConsommationDesStocksAcquisReevaluesALaJusteValeur"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_AjustementsPourImpactDeLaConsommationDesStocksAcquisReevaluesALaJusteValeur_000b1061-e7b7-46fa-8e89-f891623d3dedNotDimensionallyQualified" xlink:type="arc" order="99"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherAdjustmentsToReconcileProfitLoss_6b0303fb-078f-470d-aa78-8c1a84395887NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherAdjustmentsToReconcileProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_OtherAdjustmentsToReconcileProfitLoss_6b0303fb-078f-470d-aa78-8c1a84395887NotDimensionallyQualified" xlink:type="arc" order="100"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CashFlowsFromUsedInOperationsBeforeChangesInWorkingCapital_b3d8d969-5fe6-4e22-beea-fbebaf373395NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashFlowsFromUsedInOperationsBeforeChangesInWorkingCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CashFlowsFromUsedInOperationsBeforeChangesInWorkingCapital_b3d8d969-5fe6-4e22-beea-fbebaf373395NotDimensionallyQualified" xlink:type="arc" order="101"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AdjustmentsForDecreaseIncreaseInInventories_4ce5c6ca-011e-41a9-8e1e-ca1241ded455NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForDecreaseIncreaseInInventories"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_AdjustmentsForDecreaseIncreaseInInventories_4ce5c6ca-011e-41a9-8e1e-ca1241ded455NotDimensionallyQualified" xlink:type="arc" order="102"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AdjustmentsForDecreaseIncreaseInTradeAccountReceivable_dbbc4d99-725c-4de3-a808-546295945b66NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForDecreaseIncreaseInTradeAccountReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_AdjustmentsForDecreaseIncreaseInTradeAccountReceivable_dbbc4d99-725c-4de3-a808-546295945b66NotDimensionallyQualified" xlink:type="arc" order="103"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AdjustmentsForIncreaseDecreaseInTradeAccountPayable_2e394d3f-9cfa-4939-b1f5-b072c3d225f7NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForIncreaseDecreaseInTradeAccountPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_AdjustmentsForIncreaseDecreaseInTradeAccountPayable_2e394d3f-9cfa-4939-b1f5-b072c3d225f7NotDimensionallyQualified" xlink:type="arc" order="104"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AjustementsPourVariationDesAutresActifsCourantsEtAutresPassifsCourants_66bb22fe-b256-443c-a6e7-3e7d42ddd189NotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_AjustementsPourVariationDesAutresActifsCourantsEtAutresPassifsCourants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_AjustementsPourVariationDesAutresActifsCourantsEtAutresPassifsCourants_66bb22fe-b256-443c-a6e7-3e7d42ddd189NotDimensionallyQualified" xlink:type="arc" order="105"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities_e6b46d7d-34af-4a09-9b54-b45776931fb1NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashFlowsFromUsedInOperatingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities_e6b46d7d-34af-4a09-9b54-b45776931fb1NotDimensionallyQualified" xlink:type="arc" order="106"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_PurchaseOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets_f3f30c65-ffe6-49fe-8181-20fcb451179dNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PurchaseOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_PurchaseOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets_f3f30c65-ffe6-49fe-8181-20fcb451179dNotDimensionallyQualified" xlink:type="arc" order="107"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CashFlowsUsedInObtainingControlOfSubsidiariesOrOtherBusinessesClassifiedAsInvestingActivities_8e11db0a-88dd-483b-b666-e13a4e09d05bNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashFlowsUsedInObtainingControlOfSubsidiariesOrOtherBusinessesClassifiedAsInvestingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CashFlowsUsedInObtainingControlOfSubsidiariesOrOtherBusinessesClassifiedAsInvestingActivities_8e11db0a-88dd-483b-b666-e13a4e09d05bNotDimensionallyQualified" xlink:type="arc" order="108"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_PurchaseOfFinancialInstrumentsClassifiedAsInvestingActivities_182d0b77-6ce7-4f40-9088-f4ebe0c371f1NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PurchaseOfFinancialInstrumentsClassifiedAsInvestingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_PurchaseOfFinancialInstrumentsClassifiedAsInvestingActivities_182d0b77-6ce7-4f40-9088-f4ebe0c371f1NotDimensionallyQualified" xlink:type="arc" order="109"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProceedsFromDisposalsOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets_65f1a41d-1567-45df-9a23-2f7f9f953346NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProceedsFromDisposalsOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ProceedsFromDisposalsOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets_65f1a41d-1567-45df-9a23-2f7f9f953346NotDimensionallyQualified" xlink:type="arc" order="110"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProceedsFromSalesOfInvestmentsAccountedForUsingEquityMethod_5ce43e57-de86-4b98-9165-90855c45e4f4NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProceedsFromSalesOfInvestmentsAccountedForUsingEquityMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ProceedsFromSalesOfInvestmentsAccountedForUsingEquityMethod_5ce43e57-de86-4b98-9165-90855c45e4f4NotDimensionallyQualified" xlink:type="arc" order="111"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_VariationDesAutresActifsNonCourants_9c0eeff8-dd4c-4a16-8b26-debe926b0e27NotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_VariationDesAutresActifsNonCourants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_VariationDesAutresActifsNonCourants_9c0eeff8-dd4c-4a16-8b26-debe926b0e27NotDimensionallyQualified" xlink:type="arc" order="112"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CashFlowsFromUsedInInvestingActivities_45bd4231-0c35-4785-b568-9885e6eb4004NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashFlowsFromUsedInInvestingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CashFlowsFromUsedInInvestingActivities_45bd4231-0c35-4785-b568-9885e6eb4004NotDimensionallyQualified" xlink:type="arc" order="113"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_FluxDeTresorerieNetsLiesALoperationDechangeDeLactiviteSanteAnimaleContreLactiviteSanteGrandPublic_4fe596c0-fa54-4fdc-8f88-ce9a74ba3968NotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_FluxDeTresorerieNetsLiesALoperationDechangeDeLactiviteSanteAnimaleContreLactiviteSanteGrandPublic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_FluxDeTresorerieNetsLiesALoperationDechangeDeLactiviteSanteAnimaleContreLactiviteSanteGrandPublic_4fe596c0-fa54-4fdc-8f88-ce9a74ba3968NotDimensionallyQualified" xlink:type="arc" order="114"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProceedsFromIssuingShares_67d5839e-2ea8-4823-8244-c54aa73cfd25NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProceedsFromIssuingShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ProceedsFromIssuingShares_67d5839e-2ea8-4823-8244-c54aa73cfd25NotDimensionallyQualified" xlink:type="arc" order="115"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DividendsPaidToEquityHoldersOfParentClassifiedAsFinancingActivities_8e13cd64-bbe0-4eff-ad7d-040ef450db6fNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DividendsPaidToEquityHoldersOfParentClassifiedAsFinancingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_DividendsPaidToEquityHoldersOfParentClassifiedAsFinancingActivities_8e13cd64-bbe0-4eff-ad7d-040ef450db6fNotDimensionallyQualified" xlink:type="arc" order="116"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DividendsPaidToNoncontrollingInterestsClassifiedAsFinancingActivities_e8df5caa-9582-4537-8ab3-f0e1831f3243NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DividendsPaidToNoncontrollingInterestsClassifiedAsFinancingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_DividendsPaidToNoncontrollingInterestsClassifiedAsFinancingActivities_e8df5caa-9582-4537-8ab3-f0e1831f3243NotDimensionallyQualified" xlink:type="arc" order="117"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_PaymentsFromChangesInOwnershipInterestsInSubsidiaries_4ff0466a-bc4b-452f-abf5-8a72f16807d0NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PaymentsFromChangesInOwnershipInterestsInSubsidiaries"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_PaymentsFromChangesInOwnershipInterestsInSubsidiaries_4ff0466a-bc4b-452f-abf5-8a72f16807d0NotDimensionallyQualified" xlink:type="arc" order="118"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProceedsFromNoncurrentBorrowings_b0bfa5a4-44bc-4741-b151-2a31dc499265NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProceedsFromNoncurrentBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_ProceedsFromNoncurrentBorrowings_b0bfa5a4-44bc-4741-b151-2a31dc499265NotDimensionallyQualified" xlink:type="arc" order="119"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RepaymentsOfNoncurrentBorrowings_5f188f03-3e4a-4c50-ba7d-07618292f274NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RepaymentsOfNoncurrentBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_RepaymentsOfNoncurrentBorrowings_5f188f03-3e4a-4c50-ba7d-07618292f274NotDimensionallyQualified" xlink:type="arc" order="120"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_PaymentsOfLeaseLiabilitiesClassifiedAsFinancingActivities_59044882-03af-4463-bac5-e513eff2245aNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PaymentsOfLeaseLiabilitiesClassifiedAsFinancingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_PaymentsOfLeaseLiabilitiesClassifiedAsFinancingActivities_59044882-03af-4463-bac5-e513eff2245aNotDimensionallyQualified" xlink:type="arc" order="121"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_FluxDeTresorerieResultantUtilisesDansLeCadreDempruntsAMoinsDunAnEtAutresInstrumentsFinanciers_692cb005-00b4-45ad-94b3-3bccebe504f6NotDimensionallyQualified" xlink:href="sny-2021-12-31.xsd#sny_FluxDeTresorerieResultantUtilisesDansLeCadreDempruntsAMoinsDunAnEtAutresInstrumentsFinanciers"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_sny_FluxDeTresorerieResultantUtilisesDansLeCadreDempruntsAMoinsDunAnEtAutresInstrumentsFinanciers_692cb005-00b4-45ad-94b3-3bccebe504f6NotDimensionallyQualified" xlink:type="arc" order="122"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_PaymentsToAcquireOrRedeemEntitysShares_1dd544b7-5fc5-41be-9ca6-52bdb2a09371NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PaymentsToAcquireOrRedeemEntitysShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_PaymentsToAcquireOrRedeemEntitysShares_1dd544b7-5fc5-41be-9ca6-52bdb2a09371NotDimensionallyQualified" xlink:type="arc" order="123"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CashFlowsFromUsedInFinancingActivities_27be80d3-a8b8-4804-9af8-020c03a7f58bNotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashFlowsFromUsedInFinancingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_CashFlowsFromUsedInFinancingActivities_27be80d3-a8b8-4804-9af8-020c03a7f58bNotDimensionallyQualified" xlink:type="arc" order="124"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_EffectOfExchangeRateChangesOnCashAndCashEquivalents_a98afcd1-e60b-4c16-9353-0ae5dabf0f16NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_EffectOfExchangeRateChangesOnCashAndCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_EffectOfExchangeRateChangesOnCashAndCashEquivalents_a98afcd1-e60b-4c16-9353-0ae5dabf0f16NotDimensionallyQualified" xlink:type="arc" order="125"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncreaseDecreaseInCashAndCashEquivalents_127ed5c8-16a7-4b00-8087-6e26cdf7d224NotDimensionallyQualified" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IncreaseDecreaseInCashAndCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_esef_cor_LineItemsNotDimensionallyQualifiedPlaceholder" xlink:to="loc_ifrs-full_IncreaseDecreaseInCashAndCashEquivalents_127ed5c8-16a7-4b00-8087-6e26cdf7d224NotDimensionallyQualified" xlink:type="arc" order="126"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.sanofi.com/role/Anchoring" xlink:type="simple" xlink:href="sny-2021-12-31.xsd#Anchoring"/>
  <link:definitionLink xlink:role="http://www.sanofi.com/role/Anchoring" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_sny_AjustementPourProfitsPertesRealisesSurLaCessionDeParticipationsDansDesFilialesDesCoentreprisesEtDesEntreprisesAssocieesImpotsDifferes_9bd963a9-c685-440a-b436-251cabda9111" xlink:href="sny-2021-12-31.xsd#sny_AjustementPourProfitsPertesRealisesSurLaCessionDeParticipationsDansDesFilialesDesCoentreprisesEtDesEntreprisesAssocieesImpotsDifferes"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AdjustmentsForGainLossOnDisposalOfInvestmentsInSubsidiariesJointVenturesAndAssociates" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForGainLossOnDisposalOfInvestmentsInSubsidiariesJointVenturesAndAssociates"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_AdjustmentsForGainLossOnDisposalOfInvestmentsInSubsidiariesJointVenturesAndAssociates" xlink:to="loc_sny_AjustementPourProfitsPertesRealisesSurLaCessionDeParticipationsDansDesFilialesDesCoentreprisesEtDesEntreprisesAssocieesImpotsDifferes_9bd963a9-c685-440a-b436-251cabda9111" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AjustementsPourAmortissementsEtDepreciationsDesImmobilisationsCorporellesDroitsDutilisationEtImmobilisationsIncorporelles_0dca4520-ae14-40f0-a26d-73e3857c4d85" xlink:href="sny-2021-12-31.xsd#sny_AjustementsPourAmortissementsEtDepreciationsDesImmobilisationsCorporellesDroitsDutilisationEtImmobilisationsIncorporelles"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CashFlowsFromUsedInOperationsBeforeChangesInWorkingCapital" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashFlowsFromUsedInOperationsBeforeChangesInWorkingCapital"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperationsBeforeChangesInWorkingCapital" xlink:to="loc_sny_AjustementsPourAmortissementsEtDepreciationsDesImmobilisationsCorporellesDroitsDutilisationEtImmobilisationsIncorporelles_0dca4520-ae14-40f0-a26d-73e3857c4d85" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AdjustmentsForImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossPropertyPlantAndEquipment" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossPropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_sny_AjustementsPourAmortissementsEtDepreciationsDesImmobilisationsCorporellesDroitsDutilisationEtImmobilisationsIncorporelles_0dca4520-ae14-40f0-a26d-73e3857c4d85" xlink:to="loc_ifrs-full_AdjustmentsForImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossPropertyPlantAndEquipment" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AdjustmentsForDepreciationAndAmortisationExpenseAndImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLoss" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForDepreciationAndAmortisationExpenseAndImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLoss"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_sny_AjustementsPourAmortissementsEtDepreciationsDesImmobilisationsCorporellesDroitsDutilisationEtImmobilisationsIncorporelles_0dca4520-ae14-40f0-a26d-73e3857c4d85" xlink:to="loc_ifrs-full_AdjustmentsForDepreciationAndAmortisationExpenseAndImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLoss" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AjustementsPourImpactDeLaConsommationDesStocksAcquisReevaluesALaJusteValeur_c4380891-4f6c-428c-b5eb-68bd9d1c97fb" xlink:href="sny-2021-12-31.xsd#sny_AjustementsPourImpactDeLaConsommationDesStocksAcquisReevaluesALaJusteValeur"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperationsBeforeChangesInWorkingCapital" xlink:to="loc_sny_AjustementsPourImpactDeLaConsommationDesStocksAcquisReevaluesALaJusteValeur_c4380891-4f6c-428c-b5eb-68bd9d1c97fb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AjustementsPourVariationDesAutresActifsCourantsEtAutresPassifsCourants_4ab01087-8d6f-498d-aa38-d3c544f3b0ac" xlink:href="sny-2021-12-31.xsd#sny_AjustementsPourVariationDesAutresActifsCourantsEtAutresPassifsCourants"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AdjustmentsForIncreaseDecreaseInOtherCurrentLiabilities" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForIncreaseDecreaseInOtherCurrentLiabilities"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_AdjustmentsForIncreaseDecreaseInOtherCurrentLiabilities" xlink:to="loc_sny_AjustementsPourVariationDesAutresActifsCourantsEtAutresPassifsCourants_4ab01087-8d6f-498d-aa38-d3c544f3b0ac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AjustementsPourVariationDesProvisionsEtAutresPassifsNonCourants_42243bad-1863-4f6e-9cd8-f56f6d1d6afd" xlink:href="sny-2021-12-31.xsd#sny_AjustementsPourVariationDesProvisionsEtAutresPassifsNonCourants"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperationsBeforeChangesInWorkingCapital" xlink:to="loc_sny_AjustementsPourVariationDesProvisionsEtAutresPassifsNonCourants_42243bad-1863-4f6e-9cd8-f56f6d1d6afd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AugmentationDiminutionParLeBiaisDautreVariationDesInteretsNonControlantsCapitauxPropres_c88469fe-2e3d-47e1-bdd5-b18c5479e5f4" xlink:href="sny-2021-12-31.xsd#sny_AugmentationDiminutionParLeBiaisDautreVariationDesInteretsNonControlantsCapitauxPropres"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncreaseDecreaseThroughChangesInOwnershipInterestsInSubsidiariesThatDoNotResultInLossOfControl" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IncreaseDecreaseThroughChangesInOwnershipInterestsInSubsidiariesThatDoNotResultInLossOfControl"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_IncreaseDecreaseThroughChangesInOwnershipInterestsInSubsidiariesThatDoNotResultInLossOfControl" xlink:to="loc_sny_AugmentationDiminutionParLeBiaisDautreVariationDesInteretsNonControlantsCapitauxPropres_c88469fe-2e3d-47e1-bdd5-b18c5479e5f4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AugmentationDiminutionParLeBiaisDautresVariationsLieesALemissionDactionsGratuitesCapitauxPropres_78c1f302-6c5e-4eba-967d-2349715ca3da" xlink:href="sny-2021-12-31.xsd#sny_AugmentationDiminutionParLeBiaisDautresVariationsLieesALemissionDactionsGratuitesCapitauxPropres"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncreaseDecreaseThroughSharebasedPaymentTransactions" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IncreaseDecreaseThroughSharebasedPaymentTransactions"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_IncreaseDecreaseThroughSharebasedPaymentTransactions" xlink:to="loc_sny_AugmentationDiminutionParLeBiaisDautresVariationsLieesALemissionDactionsGratuitesCapitauxPropres_78c1f302-6c5e-4eba-967d-2349715ca3da" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsAugmentationDeCapitalReserveesAuxSalariesCapitauxPropres_1fd9af6a-cc0e-43a5-855b-f43654f31160" xlink:href="sny-2021-12-31.xsd#sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsAugmentationDeCapitalReserveesAuxSalariesCapitauxPropres"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_IncreaseDecreaseThroughSharebasedPaymentTransactions" xlink:to="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsAugmentationDeCapitalReserveesAuxSalariesCapitauxPropres_1fd9af6a-cc0e-43a5-855b-f43654f31160" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsEffetDimpotsLieALaLeveeDoptionsCapitauxPropres_ad7f2f20-4143-47a1-a910-db88b797bfc8" xlink:href="sny-2021-12-31.xsd#sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsEffetDimpotsLieALaLeveeDoptionsCapitauxPropres"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_IncreaseDecreaseThroughSharebasedPaymentTransactions" xlink:to="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsEffetDimpotsLieALaLeveeDoptionsCapitauxPropres_ad7f2f20-4143-47a1-a910-db88b797bfc8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsEmissionDactionsGratuitesEtAttributionDefinitiveDactionsGratuitesExistantesCapitauxPropres_b4b520a3-936f-4817-a778-023cf71b2204" xlink:href="sny-2021-12-31.xsd#sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsEmissionDactionsGratuitesEtAttributionDefinitiveDactionsGratuitesExistantesCapitauxPropres"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_IncreaseDecreaseThroughSharebasedPaymentTransactions" xlink:to="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsEmissionDactionsGratuitesEtAttributionDefinitiveDactionsGratuitesExistantesCapitauxPropres_b4b520a3-936f-4817-a778-023cf71b2204" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsValeurDesServicesObtenusDesSalariesCapitauxPropres_b2469265-9212-4dae-8186-79e3bd58b923" xlink:href="sny-2021-12-31.xsd#sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsValeurDesServicesObtenusDesSalariesCapitauxPropres"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_IncreaseDecreaseThroughSharebasedPaymentTransactions" xlink:to="loc_sny_AugmentationDiminutionParLeBiaisDePaiementsEnActionsValeurDesServicesObtenusDesSalariesCapitauxPropres_b2469265-9212-4dae-8186-79e3bd58b923" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_AutresProfitsPertesLitiges_796e26aa-f4c7-499e-b208-ae50f1750644" xlink:href="sny-2021-12-31.xsd#sny_AutresProfitsPertesLitiges"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProfitLossFromOperatingActivities" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLossFromOperatingActivities"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_ProfitLossFromOperatingActivities" xlink:to="loc_sny_AutresProfitsPertesLitiges_796e26aa-f4c7-499e-b208-ae50f1750644" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_GainsLossesOnLitigationSettlements" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_GainsLossesOnLitigationSettlements"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_sny_AutresProfitsPertesLitiges_796e26aa-f4c7-499e-b208-ae50f1750644" xlink:to="loc_ifrs-full_GainsLossesOnLitigationSettlements" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherGainsLosses" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherGainsLosses"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_sny_AutresProfitsPertesLitiges_796e26aa-f4c7-499e-b208-ae50f1750644" xlink:to="loc_ifrs-full_OtherGainsLosses" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_DividendesRecusDesSocietesNonConsolideesClassesDansLesActivitesOperationnelles_da1443dc-9777-49da-8c9d-0ee8d458783c" xlink:href="sny-2021-12-31.xsd#sny_DividendesRecusDesSocietesNonConsolideesClassesDansLesActivitesOperationnelles"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DividendsReceivedClassifiedAsOperatingActivities" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DividendsReceivedClassifiedAsOperatingActivities"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_DividendsReceivedClassifiedAsOperatingActivities" xlink:to="loc_sny_DividendesRecusDesSocietesNonConsolideesClassesDansLesActivitesOperationnelles_da1443dc-9777-49da-8c9d-0ee8d458783c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_FluxDeTresorerieNetsLiesALoperationDechangeDeLactiviteSanteAnimaleContreLactiviteSanteGrandPublic_c5520ddc-48e1-488a-b4f6-673f071fe28a" xlink:href="sny-2021-12-31.xsd#sny_FluxDeTresorerieNetsLiesALoperationDechangeDeLactiviteSanteAnimaleContreLactiviteSanteGrandPublic"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_InflowsOfCashFromInvestingActivities" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_InflowsOfCashFromInvestingActivities"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_InflowsOfCashFromInvestingActivities" xlink:to="loc_sny_FluxDeTresorerieNetsLiesALoperationDechangeDeLactiviteSanteAnimaleContreLactiviteSanteGrandPublic_c5520ddc-48e1-488a-b4f6-673f071fe28a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_FluxDeTresorerieResultantUtilisesDansLeCadreDempruntsAMoinsDunAnEtAutresInstrumentsFinanciers_36a97eff-9668-42d5-9030-c64aea050a18" xlink:href="sny-2021-12-31.xsd#sny_FluxDeTresorerieResultantUtilisesDansLeCadreDempruntsAMoinsDunAnEtAutresInstrumentsFinanciers"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CashFlowsFromUsedInFinancingActivities" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashFlowsFromUsedInFinancingActivities"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_CashFlowsFromUsedInFinancingActivities" xlink:to="loc_sny_FluxDeTresorerieResultantUtilisesDansLeCadreDempruntsAMoinsDunAnEtAutresInstrumentsFinanciers_36a97eff-9668-42d5-9030-c64aea050a18" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_PassifsCourantsLiesADesRegroupementsDentreprisesEtADesInteretsNonControlants_d68f0406-ab04-43a7-9c78-c50cfcefa987" xlink:href="sny-2021-12-31.xsd#sny_PassifsCourantsLiesADesRegroupementsDentreprisesEtADesInteretsNonControlants"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ContingentLiabilitiesRecognisedInBusinessCombination" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ContingentLiabilitiesRecognisedInBusinessCombination"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_ContingentLiabilitiesRecognisedInBusinessCombination" xlink:to="loc_sny_PassifsCourantsLiesADesRegroupementsDentreprisesEtADesInteretsNonControlants_d68f0406-ab04-43a7-9c78-c50cfcefa987" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_PassifsNonCourantsLiesADesRegroupementsDentreprisesEtADesInteretsNonControlants_3724855b-843c-4a2d-acd9-0c1ab4ff42e5" xlink:href="sny-2021-12-31.xsd#sny_PassifsNonCourantsLiesADesRegroupementsDentreprisesEtADesInteretsNonControlants"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_ContingentLiabilitiesRecognisedInBusinessCombination" xlink:to="loc_sny_PassifsNonCourantsLiesADesRegroupementsDentreprisesEtADesInteretsNonControlants_3724855b-843c-4a2d-acd9-0c1ab4ff42e5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_ProfitsPertesSurInstrumentsDeDetteEnActifsFinanciersAvantImpot_2d2464ca-0b4e-45aa-9789-25f36796ee61" xlink:href="sny-2021-12-31.xsd#sny_ProfitsPertesSurInstrumentsDeDetteEnActifsFinanciersAvantImpot"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossNetOfTax" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_OtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossNetOfTax" xlink:to="loc_sny_ProfitsPertesSurInstrumentsDeDetteEnActifsFinanciersAvantImpot_2d2464ca-0b4e-45aa-9789-25f36796ee61" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_ProvisionsEtAutresPassifsCourants_d836a36d-b9ea-41dc-bc95-133d6bc70c4b" xlink:href="sny-2021-12-31.xsd#sny_ProvisionsEtAutresPassifsCourants"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CurrentLiabilities" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentLiabilities"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_CurrentLiabilities" xlink:to="loc_sny_ProvisionsEtAutresPassifsCourants_d836a36d-b9ea-41dc-bc95-133d6bc70c4b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CurrentProvisions" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentProvisions"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_sny_ProvisionsEtAutresPassifsCourants_d836a36d-b9ea-41dc-bc95-133d6bc70c4b" xlink:to="loc_ifrs-full_CurrentProvisions" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherCurrentLiabilities" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherCurrentLiabilities"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_sny_ProvisionsEtAutresPassifsCourants_d836a36d-b9ea-41dc-bc95-133d6bc70c4b" xlink:to="loc_ifrs-full_OtherCurrentLiabilities" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_ProvisionsEtAutresPassifsNonCourants_46d6ad05-9050-43bb-bf07-fb843f82d26e" xlink:href="sny-2021-12-31.xsd#sny_ProvisionsEtAutresPassifsNonCourants"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_NoncurrentLiabilities" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentLiabilities"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_NoncurrentLiabilities" xlink:to="loc_sny_ProvisionsEtAutresPassifsNonCourants_46d6ad05-9050-43bb-bf07-fb843f82d26e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_NoncurrentProvisions" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentProvisions"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_sny_ProvisionsEtAutresPassifsNonCourants_46d6ad05-9050-43bb-bf07-fb843f82d26e" xlink:to="loc_ifrs-full_NoncurrentProvisions" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherNoncurrentLiabilities" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherNoncurrentLiabilities"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_sny_ProvisionsEtAutresPassifsNonCourants_46d6ad05-9050-43bb-bf07-fb843f82d26e" xlink:to="loc_ifrs-full_OtherNoncurrentLiabilities" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_ResultatAvantImpotsEtSocietesMisesEnEquivalence_b8102a86-39a1-495d-a8a7-50550e86c03e" xlink:href="sny-2021-12-31.xsd#sny_ResultatAvantImpotsEtSocietesMisesEnEquivalence"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProfitLossFromContinuingOperations" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLossFromContinuingOperations"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_ProfitLossFromContinuingOperations" xlink:to="loc_sny_ResultatAvantImpotsEtSocietesMisesEnEquivalence_b8102a86-39a1-495d-a8a7-50550e86c03e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProfitLossBeforeTax" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_sny_ResultatAvantImpotsEtSocietesMisesEnEquivalence_b8102a86-39a1-495d-a8a7-50550e86c03e" xlink:to="loc_ifrs-full_ProfitLossBeforeTax" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_ResultatDeBaseParActionAttribuableAuxActionnairesDeSanofi_3626da13-dcb3-4c0c-be82-e4a2df473325" xlink:href="sny-2021-12-31.xsd#sny_ResultatDeBaseParActionAttribuableAuxActionnairesDeSanofi"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_BasicEarningsLossPerShare" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_BasicEarningsLossPerShare"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_BasicEarningsLossPerShare" xlink:to="loc_sny_ResultatDeBaseParActionAttribuableAuxActionnairesDeSanofi_3626da13-dcb3-4c0c-be82-e4a2df473325" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_ResultatDilueParActionAttribuableAuxActionnairesDeSanofi_b70e5d7c-cc43-43b5-b22b-fc595f17b356" xlink:href="sny-2021-12-31.xsd#sny_ResultatDilueParActionAttribuableAuxActionnairesDeSanofi"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DilutedEarningsLossPerShare" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DilutedEarningsLossPerShare"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_DilutedEarningsLossPerShare" xlink:to="loc_sny_ResultatDilueParActionAttribuableAuxActionnairesDeSanofi_b70e5d7c-cc43-43b5-b22b-fc595f17b356" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sny_VariationDesAutresActifsNonCourants_8c68e81d-dd25-40e3-acc6-0d3e0f7c995d" xlink:href="sny-2021-12-31.xsd#sny_VariationDesAutresActifsNonCourants"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CashFlowsFromUsedInInvestingActivities" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashFlowsFromUsedInInvestingActivities"/>
    <link:definitionArc xlink:arcrole="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:from="loc_ifrs-full_CashFlowsFromUsedInInvestingActivities" xlink:to="loc_sny_VariationDesAutresActifsNonCourants_8c68e81d-dd25-40e3-acc6-0d3e0f7c995d" xlink:type="arc" order="1"/>
  </link:definitionLink>
</link:linkbase>
