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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019eac0c-ac9a-7836-a685-587a6d0bbfa2,g:572a66a0-45b3-49c4-b051-1d9d5c7efc4e-->
<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:roleRef roleURI="http://valneva.com/role/UnauditedInterimCondensedConsolidatedStatementofChangesinEquity" xlink:type="simple" xlink:href="valn-20260630.xsd#UnauditedInterimCondensedConsolidatedStatementofChangesinEquity"/>
  <link:definitionLink xlink:role="http://valneva.com/role/UnauditedInterimCondensedConsolidatedStatementofChangesinEquity" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_StatementOfChangesInEquityLineItems_019eac0c-af64-7302-96c5-d75ce923fdab" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_StatementOfChangesInEquityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_StatementOfChangesInEquityTable_019eac0c-af64-74ca-8fd3-7d24dcc41f8e" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_StatementOfChangesInEquityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_019eac0c-af64-7302-96c5-d75ce923fdab" xlink:to="loc_ifrs-full_StatementOfChangesInEquityTable_019eac0c-af64-74ca-8fd3-7d24dcc41f8e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ComponentsOfEquityAxis_019eac0c-af64-7930-8135-03fd12cb7c10" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ComponentsOfEquityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_StatementOfChangesInEquityTable_019eac0c-af64-74ca-8fd3-7d24dcc41f8e" xlink:to="loc_ifrs-full_ComponentsOfEquityAxis_019eac0c-af64-7930-8135-03fd12cb7c10" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ComponentsOfEquityDomain_019eac0c-af64-7930-8135-03fd12cb7c10_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ComponentsOfEquityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ComponentsOfEquityAxis_019eac0c-af64-7930-8135-03fd12cb7c10" xlink:to="loc_ifrs-full_ComponentsOfEquityDomain_019eac0c-af64-7930-8135-03fd12cb7c10_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ComponentsOfEquityDomain_019eac0c-af64-78b7-93c3-bf41227605df" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ComponentsOfEquityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ComponentsOfEquityAxis_019eac0c-af64-7930-8135-03fd12cb7c10" xlink:to="loc_ifrs-full_ComponentsOfEquityDomain_019eac0c-af64-78b7-93c3-bf41227605df" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IssuedCapitalMember_019eac0c-af64-7a71-8c8e-1969f6986a22" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_IssuedCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ComponentsOfEquityDomain_019eac0c-af64-78b7-93c3-bf41227605df" xlink:to="loc_ifrs-full_IssuedCapitalMember_019eac0c-af64-7a71-8c8e-1969f6986a22" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_SharePremiumMember_019eac0c-af64-73df-b2a7-ef58b44b86b4" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_SharePremiumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ComponentsOfEquityDomain_019eac0c-af64-78b7-93c3-bf41227605df" xlink:to="loc_ifrs-full_SharePremiumMember_019eac0c-af64-73df-b2a7-ef58b44b86b4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherReservesMember_019eac0c-af64-7f7c-ab33-c99e63d0442b" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_OtherReservesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ComponentsOfEquityDomain_019eac0c-af64-78b7-93c3-bf41227605df" xlink:to="loc_ifrs-full_OtherReservesMember_019eac0c-af64-7f7c-ab33-c99e63d0442b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RetainedEarningsExcludingProfitLossForReportingPeriodMember_019eac0c-af64-70ef-8036-e86e7e16cb97" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_RetainedEarningsExcludingProfitLossForReportingPeriodMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ComponentsOfEquityDomain_019eac0c-af64-78b7-93c3-bf41227605df" xlink:to="loc_ifrs-full_RetainedEarningsExcludingProfitLossForReportingPeriodMember_019eac0c-af64-70ef-8036-e86e7e16cb97" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RetainedEarningsProfitLossForReportingPeriodMember_019eac0c-af64-7f39-ac22-803a2ef49d92" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_RetainedEarningsProfitLossForReportingPeriodMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ComponentsOfEquityDomain_019eac0c-af64-78b7-93c3-bf41227605df" xlink:to="loc_ifrs-full_RetainedEarningsProfitLossForReportingPeriodMember_019eac0c-af64-7f39-ac22-803a2ef49d92" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Equity_019eac0c-af64-75d0-8d45-effa900a68e2" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_Equity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_019eac0c-af64-7302-96c5-d75ce923fdab" xlink:to="loc_ifrs-full_Equity_019eac0c-af64-75d0-8d45-effa900a68e2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ComprehensiveIncome_019eac0c-af64-7ca0-b3e9-8924a1a9e5f3" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ComprehensiveIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_019eac0c-af64-7302-96c5-d75ce923fdab" xlink:to="loc_ifrs-full_ComprehensiveIncome_019eac0c-af64-7ca0-b3e9-8924a1a9e5f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncreaseDecreaseThroughAppropriationOfRetainedEarnings_019eac0c-af64-7be3-92f5-8ce657b5e710" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_IncreaseDecreaseThroughAppropriationOfRetainedEarnings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_019eac0c-af64-7302-96c5-d75ce923fdab" xlink:to="loc_ifrs-full_IncreaseDecreaseThroughAppropriationOfRetainedEarnings_019eac0c-af64-7be3-92f5-8ce657b5e710" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ShareBasedCompensationArrangementsAbstract_019eac0c-af64-7a9b-89ee-1b5a2a4b6d88" xlink:href="valn-20260630.xsd#valn_ShareBasedCompensationArrangementsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_019eac0c-af64-7302-96c5-d75ce923fdab" xlink:to="loc_valn_ShareBasedCompensationArrangementsAbstract_019eac0c-af64-7a9b-89ee-1b5a2a4b6d88" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IncreaseDecreaseThroughShareBasedPaymentTransactionsValueOfServicesEquity_019eac0c-af64-751b-9d8b-3cc159ab3018" xlink:href="valn-20260630.xsd#valn_IncreaseDecreaseThroughShareBasedPaymentTransactionsValueOfServicesEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_ShareBasedCompensationArrangementsAbstract_019eac0c-af64-7a9b-89ee-1b5a2a4b6d88" xlink:to="loc_valn_IncreaseDecreaseThroughShareBasedPaymentTransactionsValueOfServicesEquity_019eac0c-af64-751b-9d8b-3cc159ab3018" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncreaseDecreaseThroughSharebasedPaymentTransactions_019eac0c-af64-701c-b3a6-8176b9142aa8" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_IncreaseDecreaseThroughSharebasedPaymentTransactions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_ShareBasedCompensationArrangementsAbstract_019eac0c-af64-7a9b-89ee-1b5a2a4b6d88" xlink:to="loc_ifrs-full_IncreaseDecreaseThroughSharebasedPaymentTransactions_019eac0c-af64-701c-b3a6-8176b9142aa8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IssueOfEquity_019eac0c-af64-7171-8b67-4842b1abdc02" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_IssueOfEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_019eac0c-af64-7302-96c5-d75ce923fdab" xlink:to="loc_ifrs-full_IssueOfEquity_019eac0c-af64-7171-8b67-4842b1abdc02" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ShareIssueRelatedCost_019eac0c-af64-71ea-aa1d-b115d3d7cde3" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ShareIssueRelatedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_019eac0c-af64-7302-96c5-d75ce923fdab" xlink:to="loc_ifrs-full_ShareIssueRelatedCost_019eac0c-af64-71ea-aa1d-b115d3d7cde3" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Equity_019eac0c-af64-79ca-bc2d-91c30923d9d0" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_Equity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/GeneralinformationNarrativeDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#GeneralinformationNarrativeDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/GeneralinformationNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_valn_DisclosureOfGeneralInformationLineItems_019fa951-b34a-71ad-9f7e-384a0f899f4e" xlink:href="valn-20260630.xsd#valn_DisclosureOfGeneralInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_DisclosureOfGeneralInformationTable_019eac0c-af64-7366-9195-f2848a52bd6d" xlink:href="valn-20260630.xsd#valn_DisclosureOfGeneralInformationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_valn_DisclosureOfGeneralInformationLineItems_019fa951-b34a-71ad-9f7e-384a0f899f4e" xlink:to="loc_valn_DisclosureOfGeneralInformationTable_019eac0c-af64-7366-9195-f2848a52bd6d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesAxis_019fa951-b34a-766f-bed2-f84c31059bc8" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_valn_DisclosureOfGeneralInformationTable_019eac0c-af64-7366-9195-f2848a52bd6d" xlink:to="loc_ifrs-full_ProductsAndServicesAxis_019fa951-b34a-766f-bed2-f84c31059bc8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019fa951-b34a-766f-bed2-f84c31059bc8_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019fa951-b34a-766f-bed2-f84c31059bc8" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019fa951-b34a-766f-bed2-f84c31059bc8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019fa951-b34a-7e9e-baff-a8b0d8abeb1f" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019fa951-b34a-766f-bed2-f84c31059bc8" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019fa951-b34a-7e9e-baff-a8b0d8abeb1f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IXIAROIXCHIQAndDUKORALMember_019fa951-b34a-7e4b-a14f-5a1948f68565" xlink:href="valn-20260630.xsd#valn_IXIAROIXCHIQAndDUKORALMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019fa951-b34a-7e9e-baff-a8b0d8abeb1f" xlink:to="loc_valn_IXIAROIXCHIQAndDUKORALMember_019fa951-b34a-7e4b-a14f-5a1948f68565" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IXCHIQMember_019fbcd4-3aa6-7cd3-b268-a8774394f562" xlink:href="valn-20260630.xsd#valn_IXCHIQMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019fa951-b34a-7e9e-baff-a8b0d8abeb1f" xlink:to="loc_valn_IXCHIQMember_019fbcd4-3aa6-7cd3-b268-a8774394f562" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_LymeVLA15Member_019fc6bc-b3ea-7008-b8c5-1ab20e8f4e68" xlink:href="valn-20260630.xsd#valn_LymeVLA15Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019fa951-b34a-7e9e-baff-a8b0d8abeb1f" xlink:to="loc_valn_LymeVLA15Member_019fc6bc-b3ea-7008-b8c5-1ab20e8f4e68" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_019fa951-f0b2-7659-ae1e-9e89448a9e30" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_valn_DisclosureOfGeneralInformationTable_019eac0c-af64-7366-9195-f2848a52bd6d" xlink:to="loc_srt_StatementGeographicalAxis_019fa951-f0b2-7659-ae1e-9e89448a9e30" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019fa951-f0b2-7659-ae1e-9e89448a9e30_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_019fa951-f0b2-7659-ae1e-9e89448a9e30" xlink:to="loc_srt_SegmentGeographicalDomain_019fa951-f0b2-7659-ae1e-9e89448a9e30_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019fa951-f0b2-710b-aa46-f72860c77c4c" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_019fa951-f0b2-7659-ae1e-9e89448a9e30" xlink:to="loc_srt_SegmentGeographicalDomain_019fa951-f0b2-710b-aa46-f72860c77c4c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_BR_019fa951-f0b2-7e80-bfae-8678de5a3c88" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_BR"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019fa951-f0b2-710b-aa46-f72860c77c4c" xlink:to="loc_country_BR_019fa951-f0b2-7e80-bfae-8678de5a3c88" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RangeAxis_019fa953-4ff7-737c-87dc-62539746eac3" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_valn_DisclosureOfGeneralInformationTable_019eac0c-af64-7366-9195-f2848a52bd6d" xlink:to="loc_ifrs-full_RangeAxis_019fa953-4ff7-737c-87dc-62539746eac3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RangeDomain_019fa953-4ff7-737c-87dc-62539746eac3_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_RangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_RangeAxis_019fa953-4ff7-737c-87dc-62539746eac3" xlink:to="loc_ifrs-full_RangeDomain_019fa953-4ff7-737c-87dc-62539746eac3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RangeDomain_019fa953-4ff7-78ed-9077-fd4a5bb19b40" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_RangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_RangeAxis_019fa953-4ff7-737c-87dc-62539746eac3" xlink:to="loc_ifrs-full_RangeDomain_019fa953-4ff7-78ed-9077-fd4a5bb19b40" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019fa953-7f30-7310-ac38-3fdefb224b86" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_RangeDomain_019fa953-4ff7-78ed-9077-fd4a5bb19b40" xlink:to="loc_srt_MaximumMember_019fa953-7f30-7310-ac38-3fdefb224b86" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019fc6f8-bc7e-7f04-9c6f-f972329a019a" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_RangeDomain_019fa953-4ff7-78ed-9077-fd4a5bb19b40" xlink:to="loc_srt_MinimumMember_019fc6f8-bc7e-7f04-9c6f-f972329a019a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019fc6bd-50cd-7806-9033-99310e8ec5bb" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_valn_DisclosureOfGeneralInformationTable_019eac0c-af64-7366-9195-f2848a52bd6d" xlink:to="loc_srt_RangeAxis_019fc6bd-50cd-7806-9033-99310e8ec5bb" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019fc6bd-50cd-7806-9033-99310e8ec5bb_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019fc6bd-50cd-7806-9033-99310e8ec5bb" xlink:to="loc_srt_RangeMember_019fc6bd-50cd-7806-9033-99310e8ec5bb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019fc6bd-50cd-78a6-8902-aead31ef13ef" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019fc6bd-50cd-7806-9033-99310e8ec5bb" xlink:to="loc_srt_RangeMember_019fc6bd-50cd-78a6-8902-aead31ef13ef" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019fc6bd-6874-7464-bce7-63a1765529fd" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019fc6bd-50cd-78a6-8902-aead31ef13ef" xlink:to="loc_srt_MinimumMember_019fc6bd-6874-7464-bce7-63a1765529fd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementScenarioAxis_019fc6f9-d59d-76c6-ad0b-5eb919b2ed8c" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StatementScenarioAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_valn_DisclosureOfGeneralInformationTable_019eac0c-af64-7366-9195-f2848a52bd6d" xlink:to="loc_srt_StatementScenarioAxis_019fc6f9-d59d-76c6-ad0b-5eb919b2ed8c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_019fc6f9-d59d-76c6-ad0b-5eb919b2ed8c_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementScenarioAxis_019fc6f9-d59d-76c6-ad0b-5eb919b2ed8c" xlink:to="loc_srt_ScenarioUnspecifiedDomain_019fc6f9-d59d-76c6-ad0b-5eb919b2ed8c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_019fc6f9-d59d-7e55-b4eb-e9f01d3499d6" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementScenarioAxis_019fc6f9-d59d-76c6-ad0b-5eb919b2ed8c" xlink:to="loc_srt_ScenarioUnspecifiedDomain_019fc6f9-d59d-7e55-b4eb-e9f01d3499d6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioForecastMember_019fc6fa-2662-76a0-88e4-81dff354606a" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScenarioForecastMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ScenarioUnspecifiedDomain_019fc6f9-d59d-7e55-b4eb-e9f01d3499d6" xlink:to="loc_srt_ScenarioForecastMember_019fc6fa-2662-76a0-88e4-81dff354606a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_NumberOfTravelVaccines_019fa951-b34a-79c2-bb91-65d28fa81db3" xlink:href="valn-20260630.xsd#valn_NumberOfTravelVaccines"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfGeneralInformationLineItems_019fa951-b34a-71ad-9f7e-384a0f899f4e" xlink:to="loc_valn_NumberOfTravelVaccines_019fa951-b34a-79c2-bb91-65d28fa81db3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_NumberOfCommercialVaccines_019fa951-b34a-7529-8a0a-23ed50582d03" xlink:href="valn-20260630.xsd#valn_NumberOfCommercialVaccines"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfGeneralInformationLineItems_019fa951-b34a-71ad-9f7e-384a0f899f4e" xlink:to="loc_valn_NumberOfCommercialVaccines_019fa951-b34a-7529-8a0a-23ed50582d03" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_NumberOfEmployees_019fa951-cd5e-728c-a68e-181f6b530d8b" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_NumberOfEmployees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfGeneralInformationLineItems_019fa951-b34a-71ad-9f7e-384a0f899f4e" xlink:to="loc_ifrs-full_NumberOfEmployees_019fa951-cd5e-728c-a68e-181f6b530d8b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_NumberOfAdultsVaccinated_019fa951-f0b2-750e-ae5c-01f0d981e36b" xlink:href="valn-20260630.xsd#valn_NumberOfAdultsVaccinated"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfGeneralInformationLineItems_019fa951-b34a-71ad-9f7e-384a0f899f4e" xlink:to="loc_valn_NumberOfAdultsVaccinated_019fa951-f0b2-750e-ae5c-01f0d981e36b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_VaccineEfficacyRate_019fa951-f0b2-7ec6-a9c4-0e11faa32d2e" xlink:href="valn-20260630.xsd#valn_VaccineEfficacyRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfGeneralInformationLineItems_019fa951-b34a-71ad-9f7e-384a0f899f4e" xlink:to="loc_valn_VaccineEfficacyRate_019fa951-f0b2-7ec6-a9c4-0e11faa32d2e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ConfidenceIntervalLevelPercentage_019fa951-f0b2-74db-8220-4d7bddc02bfe" xlink:href="valn-20260630.xsd#valn_ConfidenceIntervalLevelPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfGeneralInformationLineItems_019fa951-b34a-71ad-9f7e-384a0f899f4e" xlink:to="loc_valn_ConfidenceIntervalLevelPercentage_019fa951-f0b2-74db-8220-4d7bddc02bfe" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ReserveOfferingAmount_019fa952-0654-72e7-a9c0-764893120af5" xlink:href="valn-20260630.xsd#valn_ReserveOfferingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfGeneralInformationLineItems_019fa951-b34a-71ad-9f7e-384a0f899f4e" xlink:to="loc_valn_ReserveOfferingAmount_019fa952-0654-72e7-a9c0-764893120af5" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProceedsFromIssuingShares_019fa952-0654-7104-bb87-dccb4767ff65" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProceedsFromIssuingShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfGeneralInformationLineItems_019fa951-b34a-71ad-9f7e-384a0f899f4e" xlink:to="loc_ifrs-full_ProceedsFromIssuingShares_019fa952-0654-7104-bb87-dccb4767ff65" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_PotentialProceedsFromExerciseOfWarrants_019fa952-0654-7637-aa64-73d604c8ac48" xlink:href="valn-20260630.xsd#valn_PotentialProceedsFromExerciseOfWarrants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfGeneralInformationLineItems_019fa951-b34a-71ad-9f7e-384a0f899f4e" xlink:to="loc_valn_PotentialProceedsFromExerciseOfWarrants_019fa952-0654-7637-aa64-73d604c8ac48" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ReductionInGlobalWorkforcePercentage_019fc6f7-c380-7797-b493-f82bb3e0c153" xlink:href="valn-20260630.xsd#valn_ReductionInGlobalWorkforcePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfGeneralInformationLineItems_019fa951-b34a-71ad-9f7e-384a0f899f4e" xlink:to="loc_valn_ReductionInGlobalWorkforcePercentage_019fc6f7-c380-7797-b493-f82bb3e0c153" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/GeneralinformationSummaryofallsubsidiariesheldbythecompanydirectlyorindirectlyDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#GeneralinformationSummaryofallsubsidiariesheldbythecompanydirectlyorindirectlyDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/GeneralinformationSummaryofallsubsidiariesheldbythecompanydirectlyorindirectlyDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfSignificantInvestmentsInSubsidiariesLineItems_019eac0c-af64-734a-bd0e-c494f83c106b" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfSignificantInvestmentsInSubsidiariesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfSignificantInvestmentsInSubsidiariesTable_019eac0c-af64-7035-8956-14415e77b70c" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfSignificantInvestmentsInSubsidiariesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInSubsidiariesLineItems_019eac0c-af64-734a-bd0e-c494f83c106b" xlink:to="loc_ifrs-full_DisclosureOfSignificantInvestmentsInSubsidiariesTable_019eac0c-af64-7035-8956-14415e77b70c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_019eac0c-af64-7804-b94b-48b632a16fb2" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_SignificantInvestmentsInSubsidiariesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInSubsidiariesTable_019eac0c-af64-7035-8956-14415e77b70c" xlink:to="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_019eac0c-af64-7804-b94b-48b632a16fb2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_SignificantInvestmentsInSubsidiariesDomain_019eac0c-af64-7804-b94b-48b632a16fb2_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_SignificantInvestmentsInSubsidiariesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_019eac0c-af64-7804-b94b-48b632a16fb2" xlink:to="loc_ifrs-full_SignificantInvestmentsInSubsidiariesDomain_019eac0c-af64-7804-b94b-48b632a16fb2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_SignificantInvestmentsInSubsidiariesDomain_019eac0c-af64-73ee-bc97-bc4854500270" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_SignificantInvestmentsInSubsidiariesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_019eac0c-af64-7804-b94b-48b632a16fb2" xlink:to="loc_ifrs-full_SignificantInvestmentsInSubsidiariesDomain_019eac0c-af64-73ee-bc97-bc4854500270" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_VaccinesHoldingsSwedenABMember_019eac0c-af64-74b6-835c-a44ccd47ab77" xlink:href="valn-20260630.xsd#valn_VaccinesHoldingsSwedenABMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesDomain_019eac0c-af64-73ee-bc97-bc4854500270" xlink:to="loc_valn_VaccinesHoldingsSwedenABMember_019eac0c-af64-74b6-835c-a44ccd47ab77" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ValnevaAustriaGmbHMember_019eac0c-af64-7d7c-a775-1fa68602b801" xlink:href="valn-20260630.xsd#valn_ValnevaAustriaGmbHMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesDomain_019eac0c-af64-73ee-bc97-bc4854500270" xlink:to="loc_valn_ValnevaAustriaGmbHMember_019eac0c-af64-7d7c-a775-1fa68602b801" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ValnevaCanadaIncMember_019eac0c-af64-79a9-8a57-dfc289c99a97" xlink:href="valn-20260630.xsd#valn_ValnevaCanadaIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesDomain_019eac0c-af64-73ee-bc97-bc4854500270" xlink:to="loc_valn_ValnevaCanadaIncMember_019eac0c-af64-79a9-8a57-dfc289c99a97" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ValnevaFranceSASMember_019eac0c-af64-71af-96b3-3cb8cb3159e4" xlink:href="valn-20260630.xsd#valn_ValnevaFranceSASMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesDomain_019eac0c-af64-73ee-bc97-bc4854500270" xlink:to="loc_valn_ValnevaFranceSASMember_019eac0c-af64-71af-96b3-3cb8cb3159e4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ValnevaScotlandLtdMember_019eac0c-af64-7aac-a1ab-7791ca8ea9d4" xlink:href="valn-20260630.xsd#valn_ValnevaScotlandLtdMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesDomain_019eac0c-af64-73ee-bc97-bc4854500270" xlink:to="loc_valn_ValnevaScotlandLtdMember_019eac0c-af64-7aac-a1ab-7791ca8ea9d4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ValnevaSwedenABMember_019eac0c-af64-7b29-bac7-b33adfc3a235" xlink:href="valn-20260630.xsd#valn_ValnevaSwedenABMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesDomain_019eac0c-af64-73ee-bc97-bc4854500270" xlink:to="loc_valn_ValnevaSwedenABMember_019eac0c-af64-7b29-bac7-b33adfc3a235" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ValnevaUKLtdMember_019eac0c-af64-7f5d-8483-ca98715583e5" xlink:href="valn-20260630.xsd#valn_ValnevaUKLtdMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesDomain_019eac0c-af64-73ee-bc97-bc4854500270" xlink:to="loc_valn_ValnevaUKLtdMember_019eac0c-af64-7f5d-8483-ca98715583e5" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ValnevaUSAIncMember_019eac0c-af64-77dc-9c5e-76c60bdd48be" xlink:href="valn-20260630.xsd#valn_ValnevaUSAIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesDomain_019eac0c-af64-73ee-bc97-bc4854500270" xlink:to="loc_valn_ValnevaUSAIncMember_019eac0c-af64-77dc-9c5e-76c60bdd48be" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_VBC3ErrichtungsGmbHMember_019eac0c-af64-7398-afe0-0a8128e762e8" xlink:href="valn-20260630.xsd#valn_VBC3ErrichtungsGmbHMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesDomain_019eac0c-af64-73ee-bc97-bc4854500270" xlink:to="loc_valn_VBC3ErrichtungsGmbHMember_019eac0c-af64-7398-afe0-0a8128e762e8" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProportionOfOwnershipInterestInSubsidiary_019eac0c-af64-762b-b254-8d08793be9f0" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProportionOfOwnershipInterestInSubsidiary"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInSubsidiariesLineItems_019eac0c-af64-734a-bd0e-c494f83c106b" xlink:to="loc_ifrs-full_ProportionOfOwnershipInterestInSubsidiary_019eac0c-af64-762b-b254-8d08793be9f0" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/RevenuesDisclosureofdisaggregatedrevenuebytypeofgoodsorservicesDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#RevenuesDisclosureofdisaggregatedrevenuebytypeofgoodsorservicesDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/RevenuesDisclosureofdisaggregatedrevenuebytypeofgoodsorservicesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-719a-abd0-22a6680b2dfc" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-af64-790a-8f2b-bd0203877dab" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-719a-abd0-22a6680b2dfc" xlink:to="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-af64-790a-8f2b-bd0203877dab" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-af64-75e3-897c-2a0f7203f75d" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-af64-790a-8f2b-bd0203877dab" xlink:to="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-af64-75e3-897c-2a0f7203f75d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-75e3-897c-2a0f7203f75d_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-af64-75e3-897c-2a0f7203f75d" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-75e3-897c-2a0f7203f75d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-70b9-9787-6ab46b63b99e" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-af64-75e3-897c-2a0f7203f75d" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-70b9-9787-6ab46b63b99e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IXIAROMember_019eac0c-af64-7116-b954-5eeafbcadeb0" xlink:href="valn-20260630.xsd#valn_IXIAROMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-70b9-9787-6ab46b63b99e" xlink:to="loc_valn_IXIAROMember_019eac0c-af64-7116-b954-5eeafbcadeb0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_DUKORALMember_019eac0c-af64-7b13-8c54-4b844f300ffa" xlink:href="valn-20260630.xsd#valn_DUKORALMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-70b9-9787-6ab46b63b99e" xlink:to="loc_valn_DUKORALMember_019eac0c-af64-7b13-8c54-4b844f300ffa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ThirdPartyProductsMember_019eac0c-af64-7c46-bd51-db69329a3357" xlink:href="valn-20260630.xsd#valn_ThirdPartyProductsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-70b9-9787-6ab46b63b99e" xlink:to="loc_valn_ThirdPartyProductsMember_019eac0c-af64-7c46-bd51-db69329a3357" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IXCHIQChikungunyaVLA1553Member_019eac0c-af64-70d0-ad54-af90c00337f5" xlink:href="valn-20260630.xsd#valn_IXCHIQChikungunyaVLA1553Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-70b9-9787-6ab46b63b99e" xlink:to="loc_valn_IXCHIQChikungunyaVLA1553Member_019eac0c-af64-70d0-ad54-af90c00337f5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_RoyaltiesReceivedMember_019eac0c-af64-784c-9a6f-8b89b11fe0e7" xlink:href="valn-20260630.xsd#valn_RoyaltiesReceivedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-70b9-9787-6ab46b63b99e" xlink:to="loc_valn_RoyaltiesReceivedMember_019eac0c-af64-784c-9a6f-8b89b11fe0e7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_RevenuesFromShippingAndHandlingMember_019eac0c-af64-7781-ad74-4c1634586ea1" xlink:href="valn-20260630.xsd#valn_RevenuesFromShippingAndHandlingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-70b9-9787-6ab46b63b99e" xlink:to="loc_valn_RevenuesFromShippingAndHandlingMember_019eac0c-af64-7781-ad74-4c1634586ea1" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_MilestonePaymentLicensesMember_019eac0c-af64-7fca-b85f-639fcf6e7740" xlink:href="valn-20260630.xsd#valn_MilestonePaymentLicensesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-70b9-9787-6ab46b63b99e" xlink:to="loc_valn_MilestonePaymentLicensesMember_019eac0c-af64-7fca-b85f-639fcf6e7740" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_OthersProductsMember_019eac0c-af64-7391-94e6-abc77ea13385" xlink:href="valn-20260630.xsd#valn_OthersProductsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-70b9-9787-6ab46b63b99e" xlink:to="loc_valn_OthersProductsMember_019eac0c-af64-7391-94e6-abc77ea13385" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RevenueFromSaleOfGoods_019eac0c-af64-78bb-b9b3-3b550496db28" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_RevenueFromSaleOfGoods"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-719a-abd0-22a6680b2dfc" xlink:to="loc_ifrs-full_RevenueFromSaleOfGoods_019eac0c-af64-78bb-b9b3-3b550496db28" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_OtherRevenueFromContractWithCustomers_019eac0c-af64-7faf-a028-793ee15fbfdb" xlink:href="valn-20260630.xsd#valn_OtherRevenueFromContractWithCustomers"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-719a-abd0-22a6680b2dfc" xlink:to="loc_valn_OtherRevenueFromContractWithCustomers_019eac0c-af64-7faf-a028-793ee15fbfdb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_OtherRevenueNotFromContractsWithCustomers_019eac0c-af64-7e99-ab2a-bb311c11d1d7" xlink:href="valn-20260630.xsd#valn_OtherRevenueNotFromContractsWithCustomers"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-719a-abd0-22a6680b2dfc" xlink:to="loc_valn_OtherRevenueNotFromContractsWithCustomers_019eac0c-af64-7e99-ab2a-bb311c11d1d7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Revenue_019eac0c-af64-7536-b952-c8f8972e89c6" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_Revenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-719a-abd0-22a6680b2dfc" xlink:to="loc_ifrs-full_Revenue_019eac0c-af64-7536-b952-c8f8972e89c6" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/RevenuesNarrativeDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#RevenuesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/RevenuesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-78c2-9c7a-dbe0ebc62eb7" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-af64-7fa5-aea3-f1c2631311f3" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-78c2-9c7a-dbe0ebc62eb7" xlink:to="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-af64-7fa5-aea3-f1c2631311f3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-af64-712e-a3e4-ef01958240a1" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-af64-7fa5-aea3-f1c2631311f3" xlink:to="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-af64-712e-a3e4-ef01958240a1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-712e-a3e4-ef01958240a1_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-af64-712e-a3e4-ef01958240a1" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-712e-a3e4-ef01958240a1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-7b14-b9e4-31833d5dd71f" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-af64-712e-a3e4-ef01958240a1" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-7b14-b9e4-31833d5dd71f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IXIAROJESPECTMember_019fa965-33f3-7c97-b223-32f4b0c0b003" xlink:href="valn-20260630.xsd#valn_IXIAROJESPECTMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-7b14-b9e4-31833d5dd71f" xlink:to="loc_valn_IXIAROJESPECTMember_019fa965-33f3-7c97-b223-32f4b0c0b003" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_DUKORALMember_019eac0c-af64-7ca8-bd2b-21dd3ec8952e" xlink:href="valn-20260630.xsd#valn_DUKORALMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-7b14-b9e4-31833d5dd71f" xlink:to="loc_valn_DUKORALMember_019eac0c-af64-7ca8-bd2b-21dd3ec8952e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IXCHIQChikungunyaVLA1553Member_019eac0c-af64-7d28-90f2-c987353d60cf" xlink:href="valn-20260630.xsd#valn_IXCHIQChikungunyaVLA1553Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-7b14-b9e4-31833d5dd71f" xlink:to="loc_valn_IXCHIQChikungunyaVLA1553Member_019eac0c-af64-7d28-90f2-c987353d60cf" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ThirdPartyProductsMember_019eac0c-af64-7f73-9aa8-51391ebf537f" xlink:href="valn-20260630.xsd#valn_ThirdPartyProductsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-7b14-b9e4-31833d5dd71f" xlink:to="loc_valn_ThirdPartyProductsMember_019eac0c-af64-7f73-9aa8-51391ebf537f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IncreaseDecreaseInRevenueFromSaleOfGoods_019eac0c-af64-707e-ac3f-2795ff34097d" xlink:href="valn-20260630.xsd#valn_IncreaseDecreaseInRevenueFromSaleOfGoods"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-78c2-9c7a-dbe0ebc62eb7" xlink:to="loc_valn_IncreaseDecreaseInRevenueFromSaleOfGoods_019eac0c-af64-707e-ac3f-2795ff34097d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IncreaseDecreaseInRevenueFromSalesOfGoodsPercentage_019eac0c-af64-7068-872d-ef52e6ea6505" xlink:href="valn-20260630.xsd#valn_IncreaseDecreaseInRevenueFromSalesOfGoodsPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-78c2-9c7a-dbe0ebc62eb7" xlink:to="loc_valn_IncreaseDecreaseInRevenueFromSalesOfGoodsPercentage_019eac0c-af64-7068-872d-ef52e6ea6505" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IncreaseDecreaseInRevenueFromSaleOfGoodsThroughForeignExchangeDifferences_019fa967-26ea-7705-a697-59fa5f0cc497" xlink:href="valn-20260630.xsd#valn_IncreaseDecreaseInRevenueFromSaleOfGoodsThroughForeignExchangeDifferences"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-78c2-9c7a-dbe0ebc62eb7" xlink:to="loc_valn_IncreaseDecreaseInRevenueFromSaleOfGoodsThroughForeignExchangeDifferences_019fa967-26ea-7705-a697-59fa5f0cc497" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_OtherRevenueFromContractWithCustomers_019eac0c-af64-7ede-a112-5f99222a380f" xlink:href="valn-20260630.xsd#valn_OtherRevenueFromContractWithCustomers"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-78c2-9c7a-dbe0ebc62eb7" xlink:to="loc_valn_OtherRevenueFromContractWithCustomers_019eac0c-af64-7ede-a112-5f99222a380f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IncreaseDecreaseInRevenue_019fa96a-f180-787e-b4a0-eb09a6de4878" xlink:href="valn-20260630.xsd#valn_IncreaseDecreaseInRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-78c2-9c7a-dbe0ebc62eb7" xlink:to="loc_valn_IncreaseDecreaseInRevenue_019fa96a-f180-787e-b4a0-eb09a6de4878" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/RevenuesDisclosureofproductssalesbychannelDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#RevenuesDisclosureofproductssalesbychannelDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/RevenuesDisclosureofproductssalesbychannelDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-794a-8104-33ea89e9cacf" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-af64-78c2-ad50-57282a69ae36" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-794a-8104-33ea89e9cacf" xlink:to="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-af64-78c2-ad50-57282a69ae36" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_SalesChannelsAxis_019eac0c-af64-7331-b88a-bd4b6612008b" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_SalesChannelsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-af64-78c2-ad50-57282a69ae36" xlink:to="loc_ifrs-full_SalesChannelsAxis_019eac0c-af64-7331-b88a-bd4b6612008b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_SalesChannelsDomain_019eac0c-af64-7331-b88a-bd4b6612008b_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_SalesChannelsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_SalesChannelsAxis_019eac0c-af64-7331-b88a-bd4b6612008b" xlink:to="loc_ifrs-full_SalesChannelsDomain_019eac0c-af64-7331-b88a-bd4b6612008b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_SalesChannelsDomain_019eac0c-af64-788b-8906-a59a200de062" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_SalesChannelsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_SalesChannelsAxis_019eac0c-af64-7331-b88a-bd4b6612008b" xlink:to="loc_ifrs-full_SalesChannelsDomain_019eac0c-af64-788b-8906-a59a200de062" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_GoodsSoldDirectlyToConsumersMember_019eac0c-af64-7bab-b8f9-c1c7baed80f4" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_GoodsSoldDirectlyToConsumersMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_SalesChannelsDomain_019eac0c-af64-788b-8906-a59a200de062" xlink:to="loc_ifrs-full_GoodsSoldDirectlyToConsumersMember_019eac0c-af64-7bab-b8f9-c1c7baed80f4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_GoodsSoldThroughIntermediariesMember_019eac0c-af64-7a0d-afe6-9785cb275388" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_GoodsSoldThroughIntermediariesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_SalesChannelsDomain_019eac0c-af64-788b-8906-a59a200de062" xlink:to="loc_ifrs-full_GoodsSoldThroughIntermediariesMember_019eac0c-af64-7a0d-afe6-9785cb275388" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RevenueFromSaleOfGoods_019eac0c-af64-7865-9995-032898b7d4b7" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_RevenueFromSaleOfGoods"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-794a-8104-33ea89e9cacf" xlink:to="loc_ifrs-full_RevenueFromSaleOfGoods_019eac0c-af64-7865-9995-032898b7d4b7" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/RevenuesDisclosureofrevenuebygeographicalmarketsDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#RevenuesDisclosureofrevenuebygeographicalmarketsDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/RevenuesDisclosureofrevenuebygeographicalmarketsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-717e-9e9b-bc2f528c5a6d" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-af64-741c-a64e-1a1c8235a611" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-717e-9e9b-bc2f528c5a6d" xlink:to="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-af64-741c-a64e-1a1c8235a611" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_GeographicalAreasAxis_019eac0c-af64-733b-b2a4-216ab62f8551" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_GeographicalAreasAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-af64-741c-a64e-1a1c8235a611" xlink:to="loc_ifrs-full_GeographicalAreasAxis_019eac0c-af64-733b-b2a4-216ab62f8551" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_GeographicalAreasDomain_019eac0c-af64-733b-b2a4-216ab62f8551_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_GeographicalAreasDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_GeographicalAreasAxis_019eac0c-af64-733b-b2a4-216ab62f8551" xlink:to="loc_ifrs-full_GeographicalAreasDomain_019eac0c-af64-733b-b2a4-216ab62f8551_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_GeographicalAreasDomain_019eac0c-af64-782e-b21a-54b3d0322f1c" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_GeographicalAreasDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_GeographicalAreasAxis_019eac0c-af64-733b-b2a4-216ab62f8551" xlink:to="loc_ifrs-full_GeographicalAreasDomain_019eac0c-af64-782e-b21a-54b3d0322f1c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_019eac0c-af64-7479-8dca-e836441f118b" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_GeographicalAreasDomain_019eac0c-af64-782e-b21a-54b3d0322f1c" xlink:to="loc_country_US_019eac0c-af64-7479-8dca-e836441f118b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_019eac0c-af64-799b-9426-4f3b01565f2a" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_GeographicalAreasDomain_019eac0c-af64-782e-b21a-54b3d0322f1c" xlink:to="loc_country_CA_019eac0c-af64-799b-9426-4f3b01565f2a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_DE_019eac0c-af64-7f4f-ab76-d3ac564dcd5c" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_DE"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_GeographicalAreasDomain_019eac0c-af64-782e-b21a-54b3d0322f1c" xlink:to="loc_country_DE_019eac0c-af64-7f4f-ab76-d3ac564dcd5c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_RestOfWorldMember_019eac0c-af64-7113-98e6-4492177eb201" xlink:href="valn-20260630.xsd#valn_RestOfWorldMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_GeographicalAreasDomain_019eac0c-af64-782e-b21a-54b3d0322f1c" xlink:to="loc_valn_RestOfWorldMember_019eac0c-af64-7113-98e6-4492177eb201" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_NordicsMember_019eac0c-af64-7bff-b62c-fbc3cee877fa" xlink:href="valn-20260630.xsd#valn_NordicsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_GeographicalAreasDomain_019eac0c-af64-782e-b21a-54b3d0322f1c" xlink:to="loc_valn_NordicsMember_019eac0c-af64-7bff-b62c-fbc3cee877fa" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_GB_019eac0c-af64-79b2-bffb-30461b40b59e" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_GB"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_GeographicalAreasDomain_019eac0c-af64-782e-b21a-54b3d0322f1c" xlink:to="loc_country_GB_019eac0c-af64-79b2-bffb-30461b40b59e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_OtherEuropeMember_019eac0c-af64-7867-9ad2-0ef354b103bd" xlink:href="valn-20260630.xsd#valn_OtherEuropeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_GeographicalAreasDomain_019eac0c-af64-782e-b21a-54b3d0322f1c" xlink:to="loc_valn_OtherEuropeMember_019eac0c-af64-7867-9ad2-0ef354b103bd" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_FR_019eac0c-af64-716a-a3e5-085afcb536af" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_FR"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_GeographicalAreasDomain_019eac0c-af64-782e-b21a-54b3d0322f1c" xlink:to="loc_country_FR_019eac0c-af64-716a-a3e5-085afcb536af" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_AT_019eac0c-af64-7863-9146-ac3794611c59" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_AT"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_GeographicalAreasDomain_019eac0c-af64-782e-b21a-54b3d0322f1c" xlink:to="loc_country_AT_019eac0c-af64-7863-9146-ac3794611c59" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Revenue_019eac0c-af64-76c8-a186-eaaa0b140baa" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_Revenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-af64-717e-9e9b-bc2f528c5a6d" xlink:to="loc_ifrs-full_Revenue_019eac0c-af64-76c8-a186-eaaa0b140baa" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/OtherincomeexpensesnetNarrativeDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#OtherincomeexpensesnetNarrativeDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/OtherincomeexpensesnetNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionLineItems_019fad79-0e64-74cc-92a5-9c976e25305f" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionTable_019eac0c-af64-75dc-866c-5d06a1ec599a" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionLineItems_019fad79-0e64-74cc-92a5-9c976e25305f" xlink:to="loc_ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionTable_019eac0c-af64-75dc-866c-5d06a1ec599a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_GeographicalAreasAxis_019fad79-0e64-747a-9483-64c03ebc24f0" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_GeographicalAreasAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionTable_019eac0c-af64-75dc-866c-5d06a1ec599a" xlink:to="loc_ifrs-full_GeographicalAreasAxis_019fad79-0e64-747a-9483-64c03ebc24f0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_GeographicalAreasDomain_019fad79-0e64-747a-9483-64c03ebc24f0_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_GeographicalAreasDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_GeographicalAreasAxis_019fad79-0e64-747a-9483-64c03ebc24f0" xlink:to="loc_ifrs-full_GeographicalAreasDomain_019fad79-0e64-747a-9483-64c03ebc24f0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_GeographicalAreasDomain_019fad79-0e64-711c-ba73-5a9d19991eac" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_GeographicalAreasDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_GeographicalAreasAxis_019fad79-0e64-747a-9483-64c03ebc24f0" xlink:to="loc_ifrs-full_GeographicalAreasDomain_019fad79-0e64-711c-ba73-5a9d19991eac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_AT_019fad79-0e64-7125-88be-d470c52efc4d" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_AT"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_GeographicalAreasDomain_019fad79-0e64-711c-ba73-5a9d19991eac" xlink:to="loc_country_AT_019fad79-0e64-7125-88be-d470c52efc4d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_FR_019fad79-0e64-7e25-996e-a6b21ed48fa8" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_FR"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_GeographicalAreasDomain_019fad79-0e64-711c-ba73-5a9d19991eac" xlink:to="loc_country_FR_019fad79-0e64-7e25-996e-a6b21ed48fa8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CounterpartiesAxis_019fad7e-c786-7b8b-9621-b1d33f0130f8" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CounterpartiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionTable_019eac0c-af64-75dc-866c-5d06a1ec599a" xlink:to="loc_ifrs-full_CounterpartiesAxis_019fad7e-c786-7b8b-9621-b1d33f0130f8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CounterpartiesDomain_019fad7e-c786-7b8b-9621-b1d33f0130f8_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CounterpartiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_CounterpartiesAxis_019fad7e-c786-7b8b-9621-b1d33f0130f8" xlink:to="loc_ifrs-full_CounterpartiesDomain_019fad7e-c786-7b8b-9621-b1d33f0130f8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CounterpartiesDomain_019fad7e-c786-77f5-b8a8-d82feba89c43" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CounterpartiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_CounterpartiesAxis_019fad7e-c786-7b8b-9621-b1d33f0130f8" xlink:to="loc_ifrs-full_CounterpartiesDomain_019fad7e-c786-77f5-b8a8-d82feba89c43" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_CoalitionForEpidemicPreparednessInnovationsCEPIMember_019fad7e-c786-76d6-990c-58987e22256d" xlink:href="valn-20260630.xsd#valn_CoalitionForEpidemicPreparednessInnovationsCEPIMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_CounterpartiesDomain_019fad7e-c786-77f5-b8a8-d82feba89c43" xlink:to="loc_valn_CoalitionForEpidemicPreparednessInnovationsCEPIMember_019fad7e-c786-76d6-990c-58987e22256d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesAxis_019fad7e-c786-7260-9518-ebf39b022699" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionTable_019eac0c-af64-75dc-866c-5d06a1ec599a" xlink:to="loc_ifrs-full_ProductsAndServicesAxis_019fad7e-c786-7260-9518-ebf39b022699" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019fad7e-c786-7260-9518-ebf39b022699_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019fad7e-c786-7260-9518-ebf39b022699" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019fad7e-c786-7260-9518-ebf39b022699_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019fad7e-c786-75df-8cde-10063e074471" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019fad7e-c786-7260-9518-ebf39b022699" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019fad7e-c786-75df-8cde-10063e074471" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IXCHIQChikungunyaVLA1553Member_019fad7e-c786-7ba0-8b28-5fdba805a561" xlink:href="valn-20260630.xsd#valn_IXCHIQChikungunyaVLA1553Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019fad7e-c786-75df-8cde-10063e074471" xlink:to="loc_valn_IXCHIQChikungunyaVLA1553Member_019fad7e-c786-7ba0-8b28-5fdba805a561" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_TypesOfContractsAxis_019fad7e-c786-7050-bfd7-3dc248b2dedf" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_TypesOfContractsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionTable_019eac0c-af64-75dc-866c-5d06a1ec599a" xlink:to="loc_ifrs-full_TypesOfContractsAxis_019fad7e-c786-7050-bfd7-3dc248b2dedf" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_TypesOfContractsDomain_019fad7e-c786-7050-bfd7-3dc248b2dedf_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_TypesOfContractsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_TypesOfContractsAxis_019fad7e-c786-7050-bfd7-3dc248b2dedf" xlink:to="loc_ifrs-full_TypesOfContractsDomain_019fad7e-c786-7050-bfd7-3dc248b2dedf_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_TypesOfContractsDomain_019fad7e-c786-7d42-8a68-b2611edc5e1c" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_TypesOfContractsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_TypesOfContractsAxis_019fad7e-c786-7050-bfd7-3dc248b2dedf" xlink:to="loc_ifrs-full_TypesOfContractsDomain_019fad7e-c786-7d42-8a68-b2611edc5e1c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_StrategicPartnershipAgreementMember_019fad7e-c786-7f8b-9a0f-440cf93ffe24" xlink:href="valn-20260630.xsd#valn_StrategicPartnershipAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_TypesOfContractsDomain_019fad7e-c786-7d42-8a68-b2611edc5e1c" xlink:to="loc_valn_StrategicPartnershipAgreementMember_019fad7e-c786-7f8b-9a0f-440cf93ffe24" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IncreaseDecreaseInOtherOperatingIncomeExpense_019fad79-0e64-7c70-8249-943f8819b562" xlink:href="valn-20260630.xsd#valn_IncreaseDecreaseInOtherOperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionLineItems_019fad79-0e64-74cc-92a5-9c976e25305f" xlink:to="loc_valn_IncreaseDecreaseInOtherOperatingIncomeExpense_019fad79-0e64-7c70-8249-943f8819b562" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IncreaseDecreaseInOtherOperatingIncomeExpensePercentage_019fad79-0e64-76b1-bc96-782d153b0e77" xlink:href="valn-20260630.xsd#valn_IncreaseDecreaseInOtherOperatingIncomeExpensePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionLineItems_019fad79-0e64-74cc-92a5-9c976e25305f" xlink:to="loc_valn_IncreaseDecreaseInOtherOperatingIncomeExpensePercentage_019fad79-0e64-76b1-bc96-782d153b0e77" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherOperatingIncomeExpense_019fad79-0e64-7261-9ffa-c2b6f9f35e86" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_OtherOperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionLineItems_019fad79-0e64-74cc-92a5-9c976e25305f" xlink:to="loc_ifrs-full_OtherOperatingIncomeExpense_019fad79-0e64-7261-9ffa-c2b6f9f35e86" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IncreaseDecreaseInResearchAndDevelopmentTaxCredit_019fad79-0e64-7cce-b6ff-9d397e05c159" xlink:href="valn-20260630.xsd#valn_IncreaseDecreaseInResearchAndDevelopmentTaxCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionLineItems_019fad79-0e64-74cc-92a5-9c976e25305f" xlink:to="loc_valn_IncreaseDecreaseInResearchAndDevelopmentTaxCredit_019fad79-0e64-7cce-b6ff-9d397e05c159" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RevenueFromGovernmentGrants_019fad7e-c786-7ca2-8db3-4094817cac48" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_RevenueFromGovernmentGrants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionLineItems_019fad79-0e64-74cc-92a5-9c976e25305f" xlink:to="loc_ifrs-full_RevenueFromGovernmentGrants_019fad7e-c786-7ca2-8db3-4094817cac48" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/ImpairmenttestingDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#ImpairmenttestingDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/ImpairmenttestingDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfImpairmentLossAndReversalOfImpairmentLossLineItems_019eac0c-af64-7266-b209-2f9e3af1d40d" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfImpairmentLossAndReversalOfImpairmentLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfImpairmentLossAndReversalOfImpairmentLossTable_019eac0c-af64-7587-9187-89563316a16a" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfImpairmentLossAndReversalOfImpairmentLossTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfImpairmentLossAndReversalOfImpairmentLossLineItems_019eac0c-af64-7266-b209-2f9e3af1d40d" xlink:to="loc_ifrs-full_DisclosureOfImpairmentLossAndReversalOfImpairmentLossTable_019eac0c-af64-7587-9187-89563316a16a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis_019eac0c-af64-7a6d-8456-5984a79e0f99" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfImpairmentLossAndReversalOfImpairmentLossTable_019eac0c-af64-7587-9187-89563316a16a" xlink:to="loc_ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis_019eac0c-af64-7a6d-8456-5984a79e0f99" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CarryingAmountMember_019eac0c-af64-7a6d-8456-5984a79e0f99_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CarryingAmountMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis_019eac0c-af64-7a6d-8456-5984a79e0f99" xlink:to="loc_ifrs-full_CarryingAmountMember_019eac0c-af64-7a6d-8456-5984a79e0f99_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CarryingAmountMember_019eac0c-af64-74d6-839d-ee27e3c715c4" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CarryingAmountMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis_019eac0c-af64-7a6d-8456-5984a79e0f99" xlink:to="loc_ifrs-full_CarryingAmountMember_019eac0c-af64-74d6-839d-ee27e3c715c4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AccumulatedImpairmentMember_019eac0c-af64-734e-bb9b-bbaf528927f0" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_AccumulatedImpairmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_CarryingAmountMember_019eac0c-af64-74d6-839d-ee27e3c715c4" xlink:to="loc_ifrs-full_AccumulatedImpairmentMember_019eac0c-af64-734e-bb9b-bbaf528927f0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfAssetsAxis_019eac0c-af64-74d2-b59e-7d1c64872dd4" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfAssetsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfImpairmentLossAndReversalOfImpairmentLossTable_019eac0c-af64-7587-9187-89563316a16a" xlink:to="loc_ifrs-full_ClassesOfAssetsAxis_019eac0c-af64-74d2-b59e-7d1c64872dd4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfAssetsDomain_019eac0c-af64-74d2-b59e-7d1c64872dd4_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfAssetsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ClassesOfAssetsAxis_019eac0c-af64-74d2-b59e-7d1c64872dd4" xlink:to="loc_ifrs-full_ClassesOfAssetsDomain_019eac0c-af64-74d2-b59e-7d1c64872dd4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfAssetsDomain_019eac0c-af64-76a5-a942-16f3dd517c77" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfAssetsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ClassesOfAssetsAxis_019eac0c-af64-74d2-b59e-7d1c64872dd4" xlink:to="loc_ifrs-full_ClassesOfAssetsDomain_019eac0c-af64-76a5-a942-16f3dd517c77" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_LeaseholdImprovementsMember_019eac0c-af64-7ef6-bd5e-c706e594569f" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_LeaseholdImprovementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfAssetsDomain_019eac0c-af64-76a5-a942-16f3dd517c77" xlink:to="loc_ifrs-full_LeaseholdImprovementsMember_019eac0c-af64-7ef6-bd5e-c706e594569f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ManufacturingEquipmentMember_019eac0c-af64-7867-89fc-0a3c9cc5bdb1" xlink:href="valn-20260630.xsd#valn_ManufacturingEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfAssetsDomain_019eac0c-af64-76a5-a942-16f3dd517c77" xlink:to="loc_valn_ManufacturingEquipmentMember_019eac0c-af64-7867-89fc-0a3c9cc5bdb1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RightofuseAssetsMember_019eac0c-af64-79c8-b072-a1f23a75dbfb" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_RightofuseAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfAssetsDomain_019eac0c-af64-76a5-a942-16f3dd517c77" xlink:to="loc_ifrs-full_RightofuseAssetsMember_019eac0c-af64-79c8-b072-a1f23a75dbfb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ResearchAndDevelopmentCostsMember_019eac0c-af64-79cb-93c3-bf576c9c0bed" xlink:href="valn-20260630.xsd#valn_ResearchAndDevelopmentCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfAssetsDomain_019eac0c-af64-76a5-a942-16f3dd517c77" xlink:to="loc_valn_ResearchAndDevelopmentCostsMember_019eac0c-af64-79cb-93c3-bf576c9c0bed" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_InternalDevelopmentCostsMember_019eac0c-af64-786f-878d-8b6e6709ca93" xlink:href="valn-20260630.xsd#valn_InternalDevelopmentCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfAssetsDomain_019eac0c-af64-76a5-a942-16f3dd517c77" xlink:to="loc_valn_InternalDevelopmentCostsMember_019eac0c-af64-786f-878d-8b6e6709ca93" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Assets_019eac0c-af64-78ca-b46c-9a3da986928f" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfImpairmentLossAndReversalOfImpairmentLossLineItems_019eac0c-af64-7266-b209-2f9e3af1d40d" xlink:to="loc_ifrs-full_Assets_019eac0c-af64-78ca-b46c-9a3da986928f" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/InventoriesScheduleofinventoriesDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#InventoriesScheduleofinventoriesDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/InventoriesScheduleofinventoriesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_valn_DisclosureOfInventoriesLineItems_019fadb5-5ecd-7ae9-ac78-f20dea0e46ac" xlink:href="valn-20260630.xsd#valn_DisclosureOfInventoriesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_DisclosureOfInventoriesTable_019fadb5-5ecd-7e53-954c-609926217d57" xlink:href="valn-20260630.xsd#valn_DisclosureOfInventoriesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_valn_DisclosureOfInventoriesLineItems_019fadb5-5ecd-7ae9-ac78-f20dea0e46ac" xlink:to="loc_valn_DisclosureOfInventoriesTable_019fadb5-5ecd-7e53-954c-609926217d57" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesAxis_019fadb5-5ecd-7b58-81c2-f4f159380f83" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_valn_DisclosureOfInventoriesTable_019fadb5-5ecd-7e53-954c-609926217d57" xlink:to="loc_ifrs-full_ProductsAndServicesAxis_019fadb5-5ecd-7b58-81c2-f4f159380f83" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019fadb5-5ecd-7b58-81c2-f4f159380f83_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019fadb5-5ecd-7b58-81c2-f4f159380f83" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019fadb5-5ecd-7b58-81c2-f4f159380f83_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019fadb5-5ecd-7609-8f77-00d70c45a967" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019fadb5-5ecd-7b58-81c2-f4f159380f83" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019fadb5-5ecd-7609-8f77-00d70c45a967" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IXCHIQChikungunyaVLA1553Member_019fadb5-5ecd-73ec-9309-6256a2fb5e66" xlink:href="valn-20260630.xsd#valn_IXCHIQChikungunyaVLA1553Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019fadb5-5ecd-7609-8f77-00d70c45a967" xlink:to="loc_valn_IXCHIQChikungunyaVLA1553Member_019fadb5-5ecd-73ec-9309-6256a2fb5e66" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RawMaterials_019eac0c-af64-7401-89e3-8cde95e5b5c5" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_RawMaterials"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfInventoriesLineItems_019fadb5-5ecd-7ae9-ac78-f20dea0e46ac" xlink:to="loc_ifrs-full_RawMaterials_019eac0c-af64-7401-89e3-8cde95e5b5c5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_WorkInProgress_019eac0c-af64-7949-a236-978f0e97b955" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_WorkInProgress"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfInventoriesLineItems_019fadb5-5ecd-7ae9-ac78-f20dea0e46ac" xlink:to="loc_ifrs-full_WorkInProgress_019eac0c-af64-7949-a236-978f0e97b955" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_FinishedGoods_019eac0c-af64-706d-a70f-c9fa271c8e85" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_FinishedGoods"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfInventoriesLineItems_019fadb5-5ecd-7ae9-ac78-f20dea0e46ac" xlink:to="loc_ifrs-full_FinishedGoods_019eac0c-af64-706d-a70f-c9fa271c8e85" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_CurrentPurchasedGoods_019eac0c-af64-70b2-b1a9-0624d8f7daea" xlink:href="valn-20260630.xsd#valn_CurrentPurchasedGoods"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfInventoriesLineItems_019fadb5-5ecd-7ae9-ac78-f20dea0e46ac" xlink:to="loc_valn_CurrentPurchasedGoods_019eac0c-af64-70b2-b1a9-0624d8f7daea" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_GrossAmountOfInventoriesBeforeWriteDown_019eac0c-af64-7a49-ae9b-fd7721cf2d9c" xlink:href="valn-20260630.xsd#valn_GrossAmountOfInventoriesBeforeWriteDown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfInventoriesLineItems_019fadb5-5ecd-7ae9-ac78-f20dea0e46ac" xlink:to="loc_valn_GrossAmountOfInventoriesBeforeWriteDown_019eac0c-af64-7a49-ae9b-fd7721cf2d9c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_InventoriesWriteDownProvision_019eac0c-af64-702a-8311-adc9a027d791" xlink:href="valn-20260630.xsd#valn_InventoriesWriteDownProvision"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfInventoriesLineItems_019fadb5-5ecd-7ae9-ac78-f20dea0e46ac" xlink:to="loc_valn_InventoriesWriteDownProvision_019eac0c-af64-702a-8311-adc9a027d791" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Inventories_019eac0c-af64-71b0-847e-de473a89d966" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_Inventories"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfInventoriesLineItems_019fadb5-5ecd-7ae9-ac78-f20dea0e46ac" xlink:to="loc_ifrs-full_Inventories_019eac0c-af64-71b0-847e-de473a89d966" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/InventoriesNarrativeDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#InventoriesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/InventoriesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_valn_DisclosureOfInventoriesLineItems_019eac0c-af64-7a71-b155-9685f64ee99d" xlink:href="valn-20260630.xsd#valn_DisclosureOfInventoriesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_DisclosureOfInventoriesTable_019eac0c-af64-7397-b100-5764e8b93658" xlink:href="valn-20260630.xsd#valn_DisclosureOfInventoriesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_valn_DisclosureOfInventoriesLineItems_019eac0c-af64-7a71-b155-9685f64ee99d" xlink:to="loc_valn_DisclosureOfInventoriesTable_019eac0c-af64-7397-b100-5764e8b93658" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-af64-7712-86ac-885d018d7f47" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_valn_DisclosureOfInventoriesTable_019eac0c-af64-7397-b100-5764e8b93658" xlink:to="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-af64-7712-86ac-885d018d7f47" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-7712-86ac-885d018d7f47_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-af64-7712-86ac-885d018d7f47" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-7712-86ac-885d018d7f47_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-7b98-8953-8fe70d149677" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-af64-7712-86ac-885d018d7f47" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-7b98-8953-8fe70d149677" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_CovidVLA2001ProductNettingMember_019eac0c-af64-7647-a5e3-9264a8ffff6a" xlink:href="valn-20260630.xsd#valn_CovidVLA2001ProductNettingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-7b98-8953-8fe70d149677" xlink:to="loc_valn_CovidVLA2001ProductNettingMember_019eac0c-af64-7647-a5e3-9264a8ffff6a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IXIARODUKORALAndIXCHIQMember_019eac0c-af64-7f8b-9a69-708dfea8b09c" xlink:href="valn-20260630.xsd#valn_IXIARODUKORALAndIXCHIQMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-af64-7b98-8953-8fe70d149677" xlink:to="loc_valn_IXIARODUKORALAndIXCHIQMember_019eac0c-af64-7f8b-9a69-708dfea8b09c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_InventoriesWriteDownProvision_019eac0c-af64-7bdd-920c-4c7f894bebd8" xlink:href="valn-20260630.xsd#valn_InventoriesWriteDownProvision"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfInventoriesLineItems_019eac0c-af64-7a71-b155-9685f64ee99d" xlink:to="loc_valn_InventoriesWriteDownProvision_019eac0c-af64-7bdd-920c-4c7f894bebd8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_RawMaterialsWriteDownProvision_019eac0c-af64-7e19-a28b-1a4a7a28eb09" xlink:href="valn-20260630.xsd#valn_RawMaterialsWriteDownProvision"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfInventoriesLineItems_019eac0c-af64-7a71-b155-9685f64ee99d" xlink:to="loc_valn_RawMaterialsWriteDownProvision_019eac0c-af64-7e19-a28b-1a4a7a28eb09" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_RawMaterialsAndWorkInProgressWriteDownProvision_019eac0c-af64-75b3-abdd-1623c207da29" xlink:href="valn-20260630.xsd#valn_RawMaterialsAndWorkInProgressWriteDownProvision"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfInventoriesLineItems_019eac0c-af64-7a71-b155-9685f64ee99d" xlink:to="loc_valn_RawMaterialsAndWorkInProgressWriteDownProvision_019eac0c-af64-75b3-abdd-1623c207da29" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_FinishedGoodsWriteDownProvision_019eac0c-af64-7a7b-9d7c-53f6e73d9f72" xlink:href="valn-20260630.xsd#valn_FinishedGoodsWriteDownProvision"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfInventoriesLineItems_019eac0c-af64-7a71-b155-9685f64ee99d" xlink:to="loc_valn_FinishedGoodsWriteDownProvision_019eac0c-af64-7a7b-9d7c-53f6e73d9f72" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ShelfLifePeriod_019fd68d-e1ef-78d6-a1fb-4e95635ece1d" xlink:href="valn-20260630.xsd#valn_ShelfLifePeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_valn_DisclosureOfInventoriesLineItems_019eac0c-af64-7a71-b155-9685f64ee99d" xlink:to="loc_valn_ShelfLifePeriod_019fd68d-e1ef-78d6-a1fb-4e95635ece1d" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/TradereceivablesDisclosureofdetailedinformationabouttradereceivablesDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#TradereceivablesDisclosureofdetailedinformationabouttradereceivablesDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/TradereceivablesDisclosureofdetailedinformationabouttradereceivablesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfReconciliationOfChangesInLossAllowanceAndExplanationOfChangesInGrossCarryingAmountForFinancialInstrumentsLineItems_019eac0c-af64-7baf-a122-b16cddd04934" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfReconciliationOfChangesInLossAllowanceAndExplanationOfChangesInGrossCarryingAmountForFinancialInstrumentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfReconciliationOfChangesInLossAllowanceAndExplanationOfChangesInGrossCarryingAmountForFinancialInstrumentsTable_019eac0c-af64-7c9a-9079-f308d28bbb56" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfReconciliationOfChangesInLossAllowanceAndExplanationOfChangesInGrossCarryingAmountForFinancialInstrumentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfReconciliationOfChangesInLossAllowanceAndExplanationOfChangesInGrossCarryingAmountForFinancialInstrumentsLineItems_019eac0c-af64-7baf-a122-b16cddd04934" xlink:to="loc_ifrs-full_DisclosureOfReconciliationOfChangesInLossAllowanceAndExplanationOfChangesInGrossCarryingAmountForFinancialInstrumentsTable_019eac0c-af64-7c9a-9079-f308d28bbb56" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis_019eac0c-af64-70ac-96ea-7e18f9468282" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfReconciliationOfChangesInLossAllowanceAndExplanationOfChangesInGrossCarryingAmountForFinancialInstrumentsTable_019eac0c-af64-7c9a-9079-f308d28bbb56" xlink:to="loc_ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis_019eac0c-af64-70ac-96ea-7e18f9468282" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CarryingAmountMember_019eac0c-af64-70ac-96ea-7e18f9468282_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CarryingAmountMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis_019eac0c-af64-70ac-96ea-7e18f9468282" xlink:to="loc_ifrs-full_CarryingAmountMember_019eac0c-af64-70ac-96ea-7e18f9468282_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CarryingAmountMember_019eac0c-af64-7235-87ca-d3ea19f72eea" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CarryingAmountMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis_019eac0c-af64-70ac-96ea-7e18f9468282" xlink:to="loc_ifrs-full_CarryingAmountMember_019eac0c-af64-7235-87ca-d3ea19f72eea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_GrossCarryingAmountMember_019eac0c-af64-701a-9b14-ab501ad36f43" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_GrossCarryingAmountMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_CarryingAmountMember_019eac0c-af64-7235-87ca-d3ea19f72eea" xlink:to="loc_ifrs-full_GrossCarryingAmountMember_019eac0c-af64-701a-9b14-ab501ad36f43" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AccumulatedImpairmentMember_019eac0c-af64-79ce-a1b4-d7126a893415" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_AccumulatedImpairmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_CarryingAmountMember_019eac0c-af64-7235-87ca-d3ea19f72eea" xlink:to="loc_ifrs-full_AccumulatedImpairmentMember_019eac0c-af64-79ce-a1b4-d7126a893415" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfFinancialInstrumentsAxis_019eac0c-af64-70ca-9462-112efdbb48dd" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfFinancialInstrumentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfReconciliationOfChangesInLossAllowanceAndExplanationOfChangesInGrossCarryingAmountForFinancialInstrumentsTable_019eac0c-af64-7c9a-9079-f308d28bbb56" xlink:to="loc_ifrs-full_ClassesOfFinancialInstrumentsAxis_019eac0c-af64-70ca-9462-112efdbb48dd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfFinancialInstrumentsDomain_019eac0c-af64-70ca-9462-112efdbb48dd_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ClassesOfFinancialInstrumentsAxis_019eac0c-af64-70ca-9462-112efdbb48dd" xlink:to="loc_ifrs-full_ClassesOfFinancialInstrumentsDomain_019eac0c-af64-70ca-9462-112efdbb48dd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfFinancialInstrumentsDomain_019eac0c-af64-7fe4-bcde-752b6e38b402" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ClassesOfFinancialInstrumentsAxis_019eac0c-af64-70ca-9462-112efdbb48dd" xlink:to="loc_ifrs-full_ClassesOfFinancialInstrumentsDomain_019eac0c-af64-7fe4-bcde-752b6e38b402" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_TradeReceivablesMember_019eac0c-af64-777b-ad0c-6b581d0ce1d1" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_TradeReceivablesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfFinancialInstrumentsDomain_019eac0c-af64-7fe4-bcde-752b6e38b402" xlink:to="loc_ifrs-full_TradeReceivablesMember_019eac0c-af64-777b-ad0c-6b581d0ce1d1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfAssetsAxis_019eac0c-af64-71d4-bd8d-7191065f9ff0" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfAssetsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfReconciliationOfChangesInLossAllowanceAndExplanationOfChangesInGrossCarryingAmountForFinancialInstrumentsTable_019eac0c-af64-7c9a-9079-f308d28bbb56" xlink:to="loc_ifrs-full_ClassesOfAssetsAxis_019eac0c-af64-71d4-bd8d-7191065f9ff0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfAssetsDomain_019eac0c-af64-71d4-bd8d-7191065f9ff0_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfAssetsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ClassesOfAssetsAxis_019eac0c-af64-71d4-bd8d-7191065f9ff0" xlink:to="loc_ifrs-full_ClassesOfAssetsDomain_019eac0c-af64-71d4-bd8d-7191065f9ff0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfAssetsDomain_019eac0c-af64-72ce-a852-4b8b8a6b26c0" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfAssetsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ClassesOfAssetsAxis_019eac0c-af64-71d4-bd8d-7191065f9ff0" xlink:to="loc_ifrs-full_ClassesOfAssetsDomain_019eac0c-af64-72ce-a852-4b8b8a6b26c0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ContractAssetsMember_019eac0c-af64-75be-bfa0-2880dfab6b7d" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ContractAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfAssetsDomain_019eac0c-af64-72ce-a852-4b8b8a6b26c0" xlink:to="loc_ifrs-full_ContractAssetsMember_019eac0c-af64-75be-bfa0-2880dfab6b7d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_FinancialAssets_019eac0c-af64-78aa-b914-44481583d5be" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_FinancialAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReconciliationOfChangesInLossAllowanceAndExplanationOfChangesInGrossCarryingAmountForFinancialInstrumentsLineItems_019eac0c-af64-7baf-a122-b16cddd04934" xlink:to="loc_ifrs-full_FinancialAssets_019eac0c-af64-78aa-b914-44481583d5be" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/EquitySharecapitalandsharepremiumNarrativeDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#EquitySharecapitalandsharepremiumNarrativeDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/EquitySharecapitalandsharepremiumNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfClassesOfShareCapitalLineItems_019fae37-59f0-7fcb-98db-c252914210af" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfClassesOfShareCapitalLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfClassesOfShareCapitalTable_019fae37-59f0-70a7-910b-2fc51fd09309" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfClassesOfShareCapitalTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfClassesOfShareCapitalLineItems_019fae37-59f0-7fcb-98db-c252914210af" xlink:to="loc_ifrs-full_DisclosureOfClassesOfShareCapitalTable_019fae37-59f0-70a7-910b-2fc51fd09309" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfShareCapitalAxis_019fae37-59f0-7f95-8433-3d9060fb8ca5" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfShareCapitalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfClassesOfShareCapitalTable_019fae37-59f0-70a7-910b-2fc51fd09309" xlink:to="loc_ifrs-full_ClassesOfShareCapitalAxis_019fae37-59f0-7f95-8433-3d9060fb8ca5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfShareCapitalDomain_019fae37-59f0-7f95-8433-3d9060fb8ca5_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfShareCapitalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ClassesOfShareCapitalAxis_019fae37-59f0-7f95-8433-3d9060fb8ca5" xlink:to="loc_ifrs-full_ClassesOfShareCapitalDomain_019fae37-59f0-7f95-8433-3d9060fb8ca5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfShareCapitalDomain_019fae37-59f0-719f-bae3-08feb8e9efa3" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfShareCapitalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ClassesOfShareCapitalAxis_019fae37-59f0-7f95-8433-3d9060fb8ca5" xlink:to="loc_ifrs-full_ClassesOfShareCapitalDomain_019fae37-59f0-719f-bae3-08feb8e9efa3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OrdinarySharesMember_019fae37-59f0-7c8f-a4ba-e3a8991cf8b7" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_OrdinarySharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfShareCapitalDomain_019fae37-59f0-719f-bae3-08feb8e9efa3" xlink:to="loc_ifrs-full_OrdinarySharesMember_019fae37-59f0-7c8f-a4ba-e3a8991cf8b7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ABSAMember_019fae37-59f0-7863-97af-313539c0e40e" xlink:href="valn-20260630.xsd#valn_ABSAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfShareCapitalDomain_019fae37-59f0-719f-bae3-08feb8e9efa3" xlink:to="loc_valn_ABSAMember_019fae37-59f0-7863-97af-313539c0e40e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementScenarioAxis_019fae37-59f0-7699-befc-6d36350704bb" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StatementScenarioAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfClassesOfShareCapitalTable_019fae37-59f0-70a7-910b-2fc51fd09309" xlink:to="loc_srt_StatementScenarioAxis_019fae37-59f0-7699-befc-6d36350704bb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_019fae37-59f0-7699-befc-6d36350704bb_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementScenarioAxis_019fae37-59f0-7699-befc-6d36350704bb" xlink:to="loc_srt_ScenarioUnspecifiedDomain_019fae37-59f0-7699-befc-6d36350704bb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_019fae37-59f0-7ef0-9451-519c863140c5" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementScenarioAxis_019fae37-59f0-7699-befc-6d36350704bb" xlink:to="loc_srt_ScenarioUnspecifiedDomain_019fae37-59f0-7ef0-9451-519c863140c5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioForecastMember_019fae37-59f0-7ec6-b4e5-f074d14df3cc" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScenarioForecastMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ScenarioUnspecifiedDomain_019fae37-59f0-7ef0-9451-519c863140c5" xlink:to="loc_srt_ScenarioForecastMember_019fae37-59f0-7ec6-b4e5-f074d14df3cc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_NumberOfSharesIssued_019fae37-59f0-7fc7-a1af-ff029ff884eb" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_NumberOfSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfClassesOfShareCapitalLineItems_019fae37-59f0-7fcb-98db-c252914210af" xlink:to="loc_ifrs-full_NumberOfSharesIssued_019fae37-59f0-7fc7-a1af-ff029ff884eb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProceedsFromIssuingShares_019fae37-59f0-7216-a694-edbd3fb12d3a" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProceedsFromIssuingShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfClassesOfShareCapitalLineItems_019fae37-59f0-7fcb-98db-c252914210af" xlink:to="loc_ifrs-full_ProceedsFromIssuingShares_019fae37-59f0-7216-a694-edbd3fb12d3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_PaymentsForShareIssueCosts_019fd1fd-fd71-7ed7-a755-77d6541acfd1" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_PaymentsForShareIssueCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfClassesOfShareCapitalLineItems_019fae37-59f0-7fcb-98db-c252914210af" xlink:to="loc_ifrs-full_PaymentsForShareIssueCosts_019fd1fd-fd71-7ed7-a755-77d6541acfd1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_EquityIssuanceSubscriptionPricePerShare_019fae37-59f0-7ac5-b4d5-38d8f6aa689f" xlink:href="valn-20260630.xsd#valn_EquityIssuanceSubscriptionPricePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfClassesOfShareCapitalLineItems_019fae37-59f0-7fcb-98db-c252914210af" xlink:to="loc_valn_EquityIssuanceSubscriptionPricePerShare_019fae37-59f0-7ac5-b4d5-38d8f6aa689f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_NumberOfSharesToBeIssuedOnExerciseOfOptionsOrWarrants_019fae37-59f0-7859-99f6-03bec6f6126f" xlink:href="valn-20260630.xsd#valn_NumberOfSharesToBeIssuedOnExerciseOfOptionsOrWarrants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfClassesOfShareCapitalLineItems_019fae37-59f0-7fcb-98db-c252914210af" xlink:to="loc_valn_NumberOfSharesToBeIssuedOnExerciseOfOptionsOrWarrants_019fae37-59f0-7859-99f6-03bec6f6126f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProceedsFromExerciseOfWarrants_019fae37-59f0-7418-bddb-3ab427664aca" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProceedsFromExerciseOfWarrants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfClassesOfShareCapitalLineItems_019fae37-59f0-7fcb-98db-c252914210af" xlink:to="loc_ifrs-full_ProceedsFromExerciseOfWarrants_019fae37-59f0-7418-bddb-3ab427664aca" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_NumberOfShareWarrantForEntityShare_019fd200-1c3a-73ce-8072-2944f467bef1" xlink:href="valn-20260630.xsd#valn_NumberOfShareWarrantForEntityShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfClassesOfShareCapitalLineItems_019fae37-59f0-7fcb-98db-c252914210af" xlink:to="loc_valn_NumberOfShareWarrantForEntityShare_019fd200-1c3a-73ce-8072-2944f467bef1" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ExercisePricePerShare_019fae37-59f0-73a1-a521-383825f15648" xlink:href="valn-20260630.xsd#valn_ExercisePricePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfClassesOfShareCapitalLineItems_019fae37-59f0-7fcb-98db-c252914210af" xlink:to="loc_valn_ExercisePricePerShare_019fae37-59f0-73a1-a521-383825f15648" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/EquityScheduleofotherreservesDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#EquityScheduleofotherreservesDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/EquityScheduleofotherreservesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae3b-2a81-7412-b527-fb8bfd3a34a4" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfReservesWithinEquityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfReservesWithinEquityTable_019fae3b-2a81-7597-9e35-e73a24399d80" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfReservesWithinEquityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae3b-2a81-7412-b527-fb8bfd3a34a4" xlink:to="loc_ifrs-full_DisclosureOfReservesWithinEquityTable_019fae3b-2a81-7597-9e35-e73a24399d80" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ComponentsOfEquityAxis_019fae3b-2a81-766c-8237-7d3714ed7ddf" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ComponentsOfEquityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityTable_019fae3b-2a81-7597-9e35-e73a24399d80" xlink:to="loc_ifrs-full_ComponentsOfEquityAxis_019fae3b-2a81-766c-8237-7d3714ed7ddf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ComponentsOfEquityDomain_019fae3b-2a81-766c-8237-7d3714ed7ddf_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ComponentsOfEquityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ComponentsOfEquityAxis_019fae3b-2a81-766c-8237-7d3714ed7ddf" xlink:to="loc_ifrs-full_ComponentsOfEquityDomain_019fae3b-2a81-766c-8237-7d3714ed7ddf_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ComponentsOfEquityDomain_019fae3b-2a81-7ba7-acd5-e8635e4e34bb" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ComponentsOfEquityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ComponentsOfEquityAxis_019fae3b-2a81-766c-8237-7d3714ed7ddf" xlink:to="loc_ifrs-full_ComponentsOfEquityDomain_019fae3b-2a81-7ba7-acd5-e8635e4e34bb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherReservesMember_019fae3b-2a81-7f1d-b25b-0b020ffb7302" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_OtherReservesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ComponentsOfEquityDomain_019fae3b-2a81-7ba7-acd5-e8635e4e34bb" xlink:to="loc_ifrs-full_OtherReservesMember_019fae3b-2a81-7f1d-b25b-0b020ffb7302" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_OtherRegulatedReservesMember_019fae3b-2a81-7ae0-b3a9-5c9f45fee6d7" xlink:href="valn-20260630.xsd#valn_OtherRegulatedReservesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_OtherReservesMember_019fae3b-2a81-7f1d-b25b-0b020ffb7302" xlink:to="loc_valn_OtherRegulatedReservesMember_019fae3b-2a81-7ae0-b3a9-5c9f45fee6d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AccumulatedOtherComprehensiveIncomeMember_019fae3b-2a81-7748-bfae-cebb8bf7f673" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_OtherReservesMember_019fae3b-2a81-7f1d-b25b-0b020ffb7302" xlink:to="loc_ifrs-full_AccumulatedOtherComprehensiveIncomeMember_019fae3b-2a81-7748-bfae-cebb8bf7f673" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_TreasurySharesMember_019fae3b-2a81-7fab-b77a-ccaa5ecb371c" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_TreasurySharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_OtherReservesMember_019fae3b-2a81-7f1d-b25b-0b020ffb7302" xlink:to="loc_ifrs-full_TreasurySharesMember_019fae3b-2a81-7fab-b77a-ccaa5ecb371c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ReserveOfSharebasedPaymentsMember_019fae3b-2a81-7d4c-b95d-bd4263a29f7e" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ReserveOfSharebasedPaymentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_OtherReservesMember_019fae3b-2a81-7f1d-b25b-0b020ffb7302" xlink:to="loc_ifrs-full_ReserveOfSharebasedPaymentsMember_019fae3b-2a81-7d4c-b95d-bd4263a29f7e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_WarrantReserveMember_019fae3e-6517-78f9-8069-77ae249f6cfc" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_WarrantReserveMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_OtherReservesMember_019fae3b-2a81-7f1d-b25b-0b020ffb7302" xlink:to="loc_ifrs-full_WarrantReserveMember_019fae3e-6517-78f9-8069-77ae249f6cfc" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_OtherRevenueReserveMember_019fae3b-2a81-7433-ac69-3ebdc05eb1ba" xlink:href="valn-20260630.xsd#valn_OtherRevenueReserveMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_OtherReservesMember_019fae3b-2a81-7f1d-b25b-0b020ffb7302" xlink:to="loc_valn_OtherRevenueReserveMember_019fae3b-2a81-7433-ac69-3ebdc05eb1ba" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherReserves_019fae3b-2a81-7919-a850-e096e06e878d" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_OtherReserves"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae3b-2a81-7412-b527-fb8bfd3a34a4" xlink:to="loc_ifrs-full_OtherReserves_019fae3b-2a81-7919-a850-e096e06e878d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherComprehensiveIncomeNetOfTaxExchangeDifferencesOnTranslation_019fae3b-2a81-794c-a78d-99beb4f89eaf" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_OtherComprehensiveIncomeNetOfTaxExchangeDifferencesOnTranslation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae3b-2a81-7412-b527-fb8bfd3a34a4" xlink:to="loc_ifrs-full_OtherComprehensiveIncomeNetOfTaxExchangeDifferencesOnTranslation_019fae3b-2a81-794c-a78d-99beb4f89eaf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherComprehensiveIncomeNetOfTaxGainsLossesOnRemeasurementsOfDefinedBenefitPlans_019fae3b-2a81-72b6-81c1-012bcf94d746" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_OtherComprehensiveIncomeNetOfTaxGainsLossesOnRemeasurementsOfDefinedBenefitPlans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae3b-2a81-7412-b527-fb8bfd3a34a4" xlink:to="loc_ifrs-full_OtherComprehensiveIncomeNetOfTaxGainsLossesOnRemeasurementsOfDefinedBenefitPlans_019fae3b-2a81-72b6-81c1-012bcf94d746" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IncreaseDecreaseThroughShareBasedPaymentTransactionsValueOfServicesEquity_019fae3b-2a81-77a4-9436-b31f6703c687" xlink:href="valn-20260630.xsd#valn_IncreaseDecreaseThroughShareBasedPaymentTransactionsValueOfServicesEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae3b-2a81-7412-b527-fb8bfd3a34a4" xlink:to="loc_valn_IncreaseDecreaseThroughShareBasedPaymentTransactionsValueOfServicesEquity_019fae3b-2a81-77a4-9436-b31f6703c687" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncreaseDecreaseThroughExerciseOfWarrantsEquity_019fae3f-7b3c-7853-a54c-a54d39012613" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_IncreaseDecreaseThroughExerciseOfWarrantsEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae3b-2a81-7412-b527-fb8bfd3a34a4" xlink:to="loc_ifrs-full_IncreaseDecreaseThroughExerciseOfWarrantsEquity_019fae3f-7b3c-7853-a54c-a54d39012613" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherReserves_019fae40-0c30-744c-885c-0f7efcfd4b94" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_OtherReserves"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/EquityWarrantreserveDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#EquityWarrantreserveDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/EquityWarrantreserveDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae45-abff-7c1a-bceb-8a106d0a30f9" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfReservesWithinEquityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfReservesWithinEquityTable_019fae45-abff-754a-b99f-b67570f942b2" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfReservesWithinEquityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae45-abff-7c1a-bceb-8a106d0a30f9" xlink:to="loc_ifrs-full_DisclosureOfReservesWithinEquityTable_019fae45-abff-754a-b99f-b67570f942b2" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfShareCapitalAxis_019fae45-abff-75d0-a868-839b0507901f" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfShareCapitalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityTable_019fae45-abff-754a-b99f-b67570f942b2" xlink:to="loc_ifrs-full_ClassesOfShareCapitalAxis_019fae45-abff-75d0-a868-839b0507901f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfShareCapitalDomain_019fae45-abff-75d0-a868-839b0507901f_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfShareCapitalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ClassesOfShareCapitalAxis_019fae45-abff-75d0-a868-839b0507901f" xlink:to="loc_ifrs-full_ClassesOfShareCapitalDomain_019fae45-abff-75d0-a868-839b0507901f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfShareCapitalDomain_019fae45-abff-7ad4-a8f3-35182bd6ca62" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfShareCapitalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ClassesOfShareCapitalAxis_019fae45-abff-75d0-a868-839b0507901f" xlink:to="loc_ifrs-full_ClassesOfShareCapitalDomain_019fae45-abff-7ad4-a8f3-35182bd6ca62" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ABSAMember_019fae45-abff-7a42-b351-f81da49bcc47" xlink:href="valn-20260630.xsd#valn_ABSAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfShareCapitalDomain_019fae45-abff-7ad4-a8f3-35182bd6ca62" xlink:to="loc_valn_ABSAMember_019fae45-abff-7a42-b351-f81da49bcc47" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_WarrantsMember_019fae4e-5816-7f0f-b7ed-0e1599c7a5f8" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_WarrantsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfShareCapitalDomain_019fae45-abff-7ad4-a8f3-35182bd6ca62" xlink:to="loc_ifrs-full_WarrantsMember_019fae4e-5816-7f0f-b7ed-0e1599c7a5f8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OrdinarySharesMember_019fae52-0c01-7685-b8bb-1f9f984f060a" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_OrdinarySharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfShareCapitalDomain_019fae45-abff-7ad4-a8f3-35182bd6ca62" xlink:to="loc_ifrs-full_OrdinarySharesMember_019fae52-0c01-7685-b8bb-1f9f984f060a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_EquityIssuanceSubscriptionPricePerShare_019fae45-ec43-7d48-a575-37cd163e6e78" xlink:href="valn-20260630.xsd#valn_EquityIssuanceSubscriptionPricePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae45-abff-7c1a-bceb-8a106d0a30f9" xlink:to="loc_valn_EquityIssuanceSubscriptionPricePerShare_019fae45-ec43-7d48-a575-37cd163e6e78" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ParValuePerShare_019fae45-267e-71fd-b7ec-cb7e60185001" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ParValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae45-abff-7c1a-bceb-8a106d0a30f9" xlink:to="loc_ifrs-full_ParValuePerShare_019fae45-267e-71fd-b7ec-cb7e60185001" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_SharePremiumPerShare_019fae47-0740-72f6-a150-ee7fa52ca014" xlink:href="valn-20260630.xsd#valn_SharePremiumPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae45-abff-7c1a-bceb-8a106d0a30f9" xlink:to="loc_valn_SharePremiumPerShare_019fae47-0740-72f6-a150-ee7fa52ca014" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_FairValuePerShare_019fae58-62e1-779a-a541-e4dfc9bb73de" xlink:href="valn-20260630.xsd#valn_FairValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae45-abff-7c1a-bceb-8a106d0a30f9" xlink:to="loc_valn_FairValuePerShare_019fae58-62e1-779a-a541-e4dfc9bb73de" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProceedsFromIssuingShares_019fae53-93b9-7b26-92c6-16c90fc8f3ab" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProceedsFromIssuingShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae45-abff-7c1a-bceb-8a106d0a30f9" xlink:to="loc_ifrs-full_ProceedsFromIssuingShares_019fae53-93b9-7b26-92c6-16c90fc8f3ab" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_NumberOfInstrumentsOtherEquityInstrumentsGranted_019fae4b-0a4c-7133-baba-2f5b7cb7878c" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_NumberOfInstrumentsOtherEquityInstrumentsGranted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae45-abff-7c1a-bceb-8a106d0a30f9" xlink:to="loc_ifrs-full_NumberOfInstrumentsOtherEquityInstrumentsGranted_019fae4b-0a4c-7133-baba-2f5b7cb7878c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_WarrantExerciseRatio_019fae54-c97c-7856-b4e8-775c806eefc3" xlink:href="valn-20260630.xsd#valn_WarrantExerciseRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae45-abff-7c1a-bceb-8a106d0a30f9" xlink:to="loc_valn_WarrantExerciseRatio_019fae54-c97c-7856-b4e8-775c806eefc3" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_WeightedAverageSharePrice2019_019fae4a-129b-7219-94c3-15a99ed0ecaa" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_WeightedAverageSharePrice2019"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae45-abff-7c1a-bceb-8a106d0a30f9" xlink:to="loc_ifrs-full_WeightedAverageSharePrice2019_019fae4a-129b-7219-94c3-15a99ed0ecaa" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ExpectedVolatilityOtherEquityInstrumentsGranted_019fae4d-8579-717a-bb6b-90b28097bd0b" xlink:href="valn-20260630.xsd#valn_ExpectedVolatilityOtherEquityInstrumentsGranted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae45-abff-7c1a-bceb-8a106d0a30f9" xlink:to="loc_valn_ExpectedVolatilityOtherEquityInstrumentsGranted_019fae4d-8579-717a-bb6b-90b28097bd0b" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ExercisePricePerShare_019fae52-0c01-7fa9-a7ed-a453ae05cd99" xlink:href="valn-20260630.xsd#valn_ExercisePricePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae45-abff-7c1a-bceb-8a106d0a30f9" xlink:to="loc_valn_ExercisePricePerShare_019fae52-0c01-7fa9-a7ed-a453ae05cd99" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ExercisePricePremiumPercentage_019fae51-d2ce-7f73-a696-6dc63ea0569b" xlink:href="valn-20260630.xsd#valn_ExercisePricePremiumPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfReservesWithinEquityLineItems_019fae45-abff-7c1a-bceb-8a106d0a30f9" xlink:to="loc_valn_ExercisePricePremiumPercentage_019fae51-d2ce-7f73-a696-6dc63ea0569b" xlink:type="arc" order="10"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/BorrowingsNarrativeDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#BorrowingsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/BorrowingsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019fae6a-01f3-715f-af85-8bc15b9fe8d1" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable_019eac0c-af64-70f2-9540-844159b8593b" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019fae6a-01f3-715f-af85-8bc15b9fe8d1" xlink:to="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable_019eac0c-af64-70f2-9540-844159b8593b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_BorrowingsByNameAxis_019fae6a-01f3-7cad-ab64-b82e034d14c6" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_BorrowingsByNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable_019eac0c-af64-70f2-9540-844159b8593b" xlink:to="loc_ifrs-full_BorrowingsByNameAxis_019fae6a-01f3-7cad-ab64-b82e034d14c6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_BorrowingsByNameDomain_019fae6a-01f3-7cad-ab64-b82e034d14c6_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_BorrowingsByNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_BorrowingsByNameAxis_019fae6a-01f3-7cad-ab64-b82e034d14c6" xlink:to="loc_ifrs-full_BorrowingsByNameDomain_019fae6a-01f3-7cad-ab64-b82e034d14c6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_BorrowingsByNameDomain_019fae6a-01f3-7244-a39a-952f313626f5" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_BorrowingsByNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_BorrowingsByNameAxis_019fae6a-01f3-7cad-ab64-b82e034d14c6" xlink:to="loc_ifrs-full_BorrowingsByNameDomain_019fae6a-01f3-7244-a39a-952f313626f5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_PharmakonLoanAgreementDue2030Member_019fae6a-231f-7070-a89f-789c107d0c65" xlink:href="valn-20260630.xsd#valn_PharmakonLoanAgreementDue2030Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_BorrowingsByNameDomain_019fae6a-01f3-7244-a39a-952f313626f5" xlink:to="loc_valn_PharmakonLoanAgreementDue2030Member_019fae6a-231f-7070-a89f-789c107d0c65" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ResearchTaxCreditMember_019fae6a-01f3-7bda-9b09-b084f3fed402" xlink:href="valn-20260630.xsd#valn_ResearchTaxCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_BorrowingsByNameDomain_019fae6a-01f3-7244-a39a-952f313626f5" xlink:to="loc_valn_ResearchTaxCreditMember_019fae6a-01f3-7bda-9b09-b084f3fed402" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_CEPIMember_019fae6a-01f3-7280-9b2c-f73eba4b5894" xlink:href="valn-20260630.xsd#valn_CEPIMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_BorrowingsByNameDomain_019fae6a-01f3-7244-a39a-952f313626f5" xlink:to="loc_valn_CEPIMember_019fae6a-01f3-7280-9b2c-f73eba4b5894" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Borrowings_019fae6a-01f3-7b33-91e6-fb56642c5e16" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_Borrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019fae6a-01f3-715f-af85-8bc15b9fe8d1" xlink:to="loc_ifrs-full_Borrowings_019fae6a-01f3-7b33-91e6-fb56642c5e16" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_NumberOfMilestonesNotExpectedToBeMet_019fc717-ea8e-7336-bdc6-352bd6ccb243" xlink:href="valn-20260630.xsd#valn_NumberOfMilestonesNotExpectedToBeMet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019fae6a-01f3-715f-af85-8bc15b9fe8d1" xlink:to="loc_valn_NumberOfMilestonesNotExpectedToBeMet_019fc717-ea8e-7336-bdc6-352bd6ccb243" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_BorrowingFacilitiesMaximumBorrowingCapacity_019fae6a-231f-7c4d-9cc8-d3e2e87297ba" xlink:href="valn-20260630.xsd#valn_BorrowingFacilitiesMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019fae6a-01f3-715f-af85-8bc15b9fe8d1" xlink:to="loc_valn_BorrowingFacilitiesMaximumBorrowingCapacity_019fae6a-231f-7c4d-9cc8-d3e2e87297ba" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProceedsFromBorrowingsClassifiedAsFinancingActivities_019fae6a-231f-799a-8132-e6cad980bff8" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProceedsFromBorrowingsClassifiedAsFinancingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019fae6a-01f3-715f-af85-8bc15b9fe8d1" xlink:to="loc_ifrs-full_ProceedsFromBorrowingsClassifiedAsFinancingActivities_019fae6a-231f-799a-8132-e6cad980bff8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_UndrawnBorrowingFacilities_019fae6a-231f-712f-aeca-2c62cec3ffcb" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_UndrawnBorrowingFacilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019fae6a-01f3-715f-af85-8bc15b9fe8d1" xlink:to="loc_ifrs-full_UndrawnBorrowingFacilities_019fae6a-231f-712f-aeca-2c62cec3ffcb" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_BorrowingsInterestRate_019fae6a-231f-77b5-b53d-b9fb628a75d3" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_BorrowingsInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019fae6a-01f3-715f-af85-8bc15b9fe8d1" xlink:to="loc_ifrs-full_BorrowingsInterestRate_019fae6a-231f-77b5-b53d-b9fb628a75d3" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_BorrowingsEffectiveInterestRate_019fae6a-231f-7446-b719-5f2df013d6e4" xlink:href="valn-20260630.xsd#valn_BorrowingsEffectiveInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019fae6a-01f3-715f-af85-8bc15b9fe8d1" xlink:to="loc_valn_BorrowingsEffectiveInterestRate_019fae6a-231f-7446-b719-5f2df013d6e4" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_BorrowingsTransactionCosts_019fae6a-231f-7d0d-b914-78b77331ba38" xlink:href="valn-20260630.xsd#valn_BorrowingsTransactionCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019fae6a-01f3-715f-af85-8bc15b9fe8d1" xlink:to="loc_valn_BorrowingsTransactionCosts_019fae6a-231f-7d0d-b914-78b77331ba38" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_PaymentsForDebtIssueCosts_019fc71c-d8b1-757b-90ab-54f07c5a360e" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_PaymentsForDebtIssueCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019fae6a-01f3-715f-af85-8bc15b9fe8d1" xlink:to="loc_ifrs-full_PaymentsForDebtIssueCosts_019fc71c-d8b1-757b-90ab-54f07c5a360e" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/BorrowingsScheduleofmaturityanalysisofnoncurrentborrowingsDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#BorrowingsScheduleofmaturityanalysisofnoncurrentborrowingsDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/BorrowingsScheduleofmaturityanalysisofnoncurrentborrowingsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7db6-8dee-1e52df934a96" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable_019eac0c-af64-731d-8e6d-1c2270fb8489" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7db6-8dee-1e52df934a96" xlink:to="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable_019eac0c-af64-731d-8e6d-1c2270fb8489" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_MaturityAxis_019eac0c-af64-7740-8aad-8b48ffa31e8d" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_MaturityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable_019eac0c-af64-731d-8e6d-1c2270fb8489" xlink:to="loc_ifrs-full_MaturityAxis_019eac0c-af64-7740-8aad-8b48ffa31e8d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_MaturityDomain_019eac0c-af64-7740-8aad-8b48ffa31e8d_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_MaturityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_MaturityAxis_019eac0c-af64-7740-8aad-8b48ffa31e8d" xlink:to="loc_ifrs-full_MaturityDomain_019eac0c-af64-7740-8aad-8b48ffa31e8d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_MaturityDomain_019eac0c-af64-7e39-bada-ed02c25d00fd" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_MaturityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_MaturityAxis_019eac0c-af64-7740-8aad-8b48ffa31e8d" xlink:to="loc_ifrs-full_MaturityDomain_019eac0c-af64-7e39-bada-ed02c25d00fd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_LaterThanOneYearAndNotLaterThanThreeYearsMember_019eac0c-af64-71f2-a813-e3d64a1c4c95" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_LaterThanOneYearAndNotLaterThanThreeYearsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_MaturityDomain_019eac0c-af64-7e39-bada-ed02c25d00fd" xlink:to="loc_ifrs-full_LaterThanOneYearAndNotLaterThanThreeYearsMember_019eac0c-af64-71f2-a813-e3d64a1c4c95" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_LaterThanThreeYearsAndNotLaterThanFiveYearsMember_019eac0c-af64-7583-87fc-eb637827227a" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_LaterThanThreeYearsAndNotLaterThanFiveYearsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_MaturityDomain_019eac0c-af64-7e39-bada-ed02c25d00fd" xlink:to="loc_ifrs-full_LaterThanThreeYearsAndNotLaterThanFiveYearsMember_019eac0c-af64-7583-87fc-eb637827227a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_LaterThanFiveYearsMember_019eac0c-af64-7f01-889b-4f35fb5f7e1d" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_LaterThanFiveYearsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_MaturityDomain_019eac0c-af64-7e39-bada-ed02c25d00fd" xlink:to="loc_ifrs-full_LaterThanFiveYearsMember_019eac0c-af64-7f01-889b-4f35fb5f7e1d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_LongtermBorrowings_019eac0c-af64-7ba5-ad9a-3c8497e3e986" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_LongtermBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7db6-8dee-1e52df934a96" xlink:to="loc_ifrs-full_LongtermBorrowings_019eac0c-af64-7ba5-ad9a-3c8497e3e986" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CurrentBorrowingsAndCurrentPortionOfNoncurrentBorrowings_019eac0c-af64-7c1c-91ce-2bed056b4248" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CurrentBorrowingsAndCurrentPortionOfNoncurrentBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7db6-8dee-1e52df934a96" xlink:to="loc_ifrs-full_CurrentBorrowingsAndCurrentPortionOfNoncurrentBorrowings_019eac0c-af64-7c1c-91ce-2bed056b4248" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Borrowings_019eac0c-af64-7c26-b30a-c9ab623afb14" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_Borrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7db6-8dee-1e52df934a96" xlink:to="loc_ifrs-full_Borrowings_019eac0c-af64-7c26-b30a-c9ab623afb14" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/BorrowingsScheduleofborrowingsbydenominatedcurrencyDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#BorrowingsScheduleofborrowingsbydenominatedcurrencyDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/BorrowingsScheduleofborrowingsbydenominatedcurrencyDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7662-a832-6216baf94f71" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable_019eac0c-af64-71b6-bfbd-4a9730577649" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7662-a832-6216baf94f71" xlink:to="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable_019eac0c-af64-71b6-bfbd-4a9730577649" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CurrencyAxis_019eac0c-af64-76b7-a4d8-faad7314158a" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_CurrencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable_019eac0c-af64-71b6-bfbd-4a9730577649" xlink:to="loc_srt_CurrencyAxis_019eac0c-af64-76b7-a4d8-faad7314158a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_currency_AllCurrenciesDomain_019eac0c-af64-76b7-a4d8-faad7314158a_default" xlink:href="https://xbrl.sec.gov/currency/2025/currency-2025.xsd#currency_AllCurrenciesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CurrencyAxis_019eac0c-af64-76b7-a4d8-faad7314158a" xlink:to="loc_currency_AllCurrenciesDomain_019eac0c-af64-76b7-a4d8-faad7314158a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_currency_AllCurrenciesDomain_019eac0c-af64-7230-807b-72d926bd3c27" xlink:href="https://xbrl.sec.gov/currency/2025/currency-2025.xsd#currency_AllCurrenciesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CurrencyAxis_019eac0c-af64-76b7-a4d8-faad7314158a" xlink:to="loc_currency_AllCurrenciesDomain_019eac0c-af64-7230-807b-72d926bd3c27" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_currency_EUR_019eac0c-af64-7eea-9aa5-7a22481c7bbe" xlink:href="https://xbrl.sec.gov/currency/2025/currency-2025.xsd#currency_EUR"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_currency_AllCurrenciesDomain_019eac0c-af64-7230-807b-72d926bd3c27" xlink:to="loc_currency_EUR_019eac0c-af64-7eea-9aa5-7a22481c7bbe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_currency_USD_019eac0c-af64-777a-a75f-13fb5a1e6982" xlink:href="https://xbrl.sec.gov/currency/2025/currency-2025.xsd#currency_USD"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_currency_AllCurrenciesDomain_019eac0c-af64-7230-807b-72d926bd3c27" xlink:to="loc_currency_USD_019eac0c-af64-777a-a75f-13fb5a1e6982" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Borrowings_019eac0c-af64-7c76-ad10-8751f2bb484b" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_Borrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7662-a832-6216baf94f71" xlink:to="loc_ifrs-full_Borrowings_019eac0c-af64-7c76-ad10-8751f2bb484b" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/BorrowingsScheduleofreconciliationofloanDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#BorrowingsScheduleofreconciliationofloanDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/BorrowingsScheduleofreconciliationofloanDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7918-b7b1-40a672aded09" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable_019eac0c-af64-7bf8-9907-dd7746b339c9" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7918-b7b1-40a672aded09" xlink:to="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable_019eac0c-af64-7bf8-9907-dd7746b339c9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_BorrowingsByNameAxis_019eac0c-af64-7053-9028-83f01cd2e86a" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_BorrowingsByNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable_019eac0c-af64-7bf8-9907-dd7746b339c9" xlink:to="loc_ifrs-full_BorrowingsByNameAxis_019eac0c-af64-7053-9028-83f01cd2e86a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_BorrowingsByNameDomain_019eac0c-af64-7053-9028-83f01cd2e86a_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_BorrowingsByNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_BorrowingsByNameAxis_019eac0c-af64-7053-9028-83f01cd2e86a" xlink:to="loc_ifrs-full_BorrowingsByNameDomain_019eac0c-af64-7053-9028-83f01cd2e86a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_BorrowingsByNameDomain_019eac0c-af64-7662-b95c-fa70a312fe6b" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_BorrowingsByNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_BorrowingsByNameAxis_019eac0c-af64-7053-9028-83f01cd2e86a" xlink:to="loc_ifrs-full_BorrowingsByNameDomain_019eac0c-af64-7662-b95c-fa70a312fe6b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_PharmakonLoanDue2030AndAmendedDebtFinancingAgreementDue2028Member_019fcbf2-8155-7d56-9726-7ee16c6acf1c" xlink:href="valn-20260630.xsd#valn_PharmakonLoanDue2030AndAmendedDebtFinancingAgreementDue2028Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_BorrowingsByNameDomain_019eac0c-af64-7662-b95c-fa70a312fe6b" xlink:to="loc_valn_PharmakonLoanDue2030AndAmendedDebtFinancingAgreementDue2028Member_019fcbf2-8155-7d56-9726-7ee16c6acf1c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Borrowings_019eac0c-af64-70cd-ac47-5b15f3e904ae" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_Borrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7918-b7b1-40a672aded09" xlink:to="loc_ifrs-full_Borrowings_019eac0c-af64-70cd-ac47-5b15f3e904ae" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_GrossProceedsFromBorrowingsClassifiedAsFinancingActivities_019f37ac-1fa8-721c-ae1c-6f2559e725ac" xlink:href="valn-20260630.xsd#valn_GrossProceedsFromBorrowingsClassifiedAsFinancingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7918-b7b1-40a672aded09" xlink:to="loc_valn_GrossProceedsFromBorrowingsClassifiedAsFinancingActivities_019f37ac-1fa8-721c-ae1c-6f2559e725ac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IncreaseDecreaseThroughTransactionCostsBorrowings_019eac0c-af64-7ac6-b39e-cc7efd3e57ae" xlink:href="valn-20260630.xsd#valn_IncreaseDecreaseThroughTransactionCostsBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7918-b7b1-40a672aded09" xlink:to="loc_valn_IncreaseDecreaseThroughTransactionCostsBorrowings_019eac0c-af64-7ac6-b39e-cc7efd3e57ae" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RepaymentsOfBorrowingsClassifiedAsFinancingActivities_019fae6b-a8f7-7d93-a4bc-bd33d4ef8bf6" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_RepaymentsOfBorrowingsClassifiedAsFinancingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7918-b7b1-40a672aded09" xlink:to="loc_ifrs-full_RepaymentsOfBorrowingsClassifiedAsFinancingActivities_019fae6b-a8f7-7d93-a4bc-bd33d4ef8bf6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_AccruedInterestOnBorrowings_019eac0c-af64-7b1b-93f6-aa0cd98ad816" xlink:href="valn-20260630.xsd#valn_AccruedInterestOnBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7918-b7b1-40a672aded09" xlink:to="loc_valn_AccruedInterestOnBorrowings_019eac0c-af64-7b1b-93f6-aa0cd98ad816" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_InterestExpenseOnBorrowings_019eac0c-af64-7429-9f85-00cbfeda656e" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_InterestExpenseOnBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7918-b7b1-40a672aded09" xlink:to="loc_ifrs-full_InterestExpenseOnBorrowings_019eac0c-af64-7429-9f85-00cbfeda656e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IncreaseDecreaseThroughExchangeRateDifferenceBorrowings_019eac0c-af64-7d23-97c6-8ce4b0b306d6" xlink:href="valn-20260630.xsd#valn_IncreaseDecreaseThroughExchangeRateDifferenceBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7918-b7b1-40a672aded09" xlink:to="loc_valn_IncreaseDecreaseThroughExchangeRateDifferenceBorrowings_019eac0c-af64-7d23-97c6-8ce4b0b306d6" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Borrowings_019eac0c-af64-7b33-9a20-f4ffd956317b" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_Borrowings"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_LongtermBorrowings_019eac0c-af64-7b9b-8283-27100fb3e33a" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_LongtermBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7918-b7b1-40a672aded09" xlink:to="loc_ifrs-full_LongtermBorrowings_019eac0c-af64-7b9b-8283-27100fb3e33a" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CurrentBorrowingsAndCurrentPortionOfNoncurrentBorrowings_019eac0c-af64-747b-83d9-c79cfab0755c" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CurrentBorrowingsAndCurrentPortionOfNoncurrentBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_019eac0c-af64-7918-b7b1-40a672aded09" xlink:to="loc_ifrs-full_CurrentBorrowingsAndCurrentPortionOfNoncurrentBorrowings_019eac0c-af64-747b-83d9-c79cfab0755c" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/ContractliabilitiesNarrativeDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#ContractliabilitiesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/ContractliabilitiesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-b068-76c8-8310-2ed2c7ef3891" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-b068-78ea-83c7-e6e2054ac5d8" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-b068-76c8-8310-2ed2c7ef3891" xlink:to="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-b068-78ea-83c7-e6e2054ac5d8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-b068-7e5e-9a47-abc7de88d4d7" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-b068-78ea-83c7-e6e2054ac5d8" xlink:to="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-b068-7e5e-9a47-abc7de88d4d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-b068-7e5e-9a47-abc7de88d4d7_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-b068-7e5e-9a47-abc7de88d4d7" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-b068-7e5e-9a47-abc7de88d4d7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-b068-72ef-b96a-4de02a4c2bc7" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-b068-7e5e-9a47-abc7de88d4d7" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-b068-72ef-b96a-4de02a4c2bc7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_AnalyticalSupportAndDrugSubstanceMember_019eac0c-b068-7560-95c9-e64ab29c3854" xlink:href="valn-20260630.xsd#valn_AnalyticalSupportAndDrugSubstanceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-b068-72ef-b96a-4de02a4c2bc7" xlink:to="loc_valn_AnalyticalSupportAndDrugSubstanceMember_019eac0c-b068-7560-95c9-e64ab29c3854" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_TypesOfContractsAxis_019eac0c-b068-7ba5-b601-de852bca9d28" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_TypesOfContractsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-b068-78ea-83c7-e6e2054ac5d8" xlink:to="loc_ifrs-full_TypesOfContractsAxis_019eac0c-b068-7ba5-b601-de852bca9d28" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_TypesOfContractsDomain_019eac0c-b068-7ba5-b601-de852bca9d28_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_TypesOfContractsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_TypesOfContractsAxis_019eac0c-b068-7ba5-b601-de852bca9d28" xlink:to="loc_ifrs-full_TypesOfContractsDomain_019eac0c-b068-7ba5-b601-de852bca9d28_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_TypesOfContractsDomain_019eac0c-b068-76e3-adcd-05e40fb66fab" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_TypesOfContractsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_TypesOfContractsAxis_019eac0c-b068-7ba5-b601-de852bca9d28" xlink:to="loc_ifrs-full_TypesOfContractsDomain_019eac0c-b068-76e3-adcd-05e40fb66fab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_LicenceAgreementWithSerumInstituteOfIndiaSIIMember_019eac0c-b068-786b-997d-11f31d25ce12" xlink:href="valn-20260630.xsd#valn_LicenceAgreementWithSerumInstituteOfIndiaSIIMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_TypesOfContractsDomain_019eac0c-b068-76e3-adcd-05e40fb66fab" xlink:to="loc_valn_LicenceAgreementWithSerumInstituteOfIndiaSIIMember_019eac0c-b068-786b-997d-11f31d25ce12" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CurrentContractLiabilities_019eac0c-b068-7a16-9a16-72d08132dde6" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CurrentContractLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-b068-76c8-8310-2ed2c7ef3891" xlink:to="loc_ifrs-full_CurrentContractLiabilities_019eac0c-b068-7a16-9a16-72d08132dde6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_RevenueRecognitionContractLiabilities_019eac0c-b068-7428-9d0d-59593e9add68" xlink:href="valn-20260630.xsd#valn_RevenueRecognitionContractLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-b068-76c8-8310-2ed2c7ef3891" xlink:to="loc_valn_RevenueRecognitionContractLiabilities_019eac0c-b068-7428-9d0d-59593e9add68" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/RefundliabilitiesNarrativeDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#RefundliabilitiesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/RefundliabilitiesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-b068-7b01-ba36-cbc18f1a9c7b" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-b068-7c0b-b6ca-a15853f8c313" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-b068-7b01-ba36-cbc18f1a9c7b" xlink:to="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-b068-7c0b-b6ca-a15853f8c313" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CounterpartiesAxis_019eac0c-b068-725e-b06b-3aac02d259f7" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CounterpartiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-b068-7c0b-b6ca-a15853f8c313" xlink:to="loc_ifrs-full_CounterpartiesAxis_019eac0c-b068-725e-b06b-3aac02d259f7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CounterpartiesDomain_019eac0c-b068-725e-b06b-3aac02d259f7_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CounterpartiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_CounterpartiesAxis_019eac0c-b068-725e-b06b-3aac02d259f7" xlink:to="loc_ifrs-full_CounterpartiesDomain_019eac0c-b068-725e-b06b-3aac02d259f7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CounterpartiesDomain_019eac0c-b068-7d61-9a02-be05196701f5" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CounterpartiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_CounterpartiesAxis_019eac0c-b068-725e-b06b-3aac02d259f7" xlink:to="loc_ifrs-full_CounterpartiesDomain_019eac0c-b068-7d61-9a02-be05196701f5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_PfizerIncMember_019eac0c-b068-7737-b7cd-05062338cb09" xlink:href="valn-20260630.xsd#valn_PfizerIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_CounterpartiesDomain_019eac0c-b068-7d61-9a02-be05196701f5" xlink:to="loc_valn_PfizerIncMember_019eac0c-b068-7737-b7cd-05062338cb09" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_GSKMember_019eac0c-b068-7a55-a4e4-5ccc9526b3ba" xlink:href="valn-20260630.xsd#valn_GSKMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_CounterpartiesDomain_019eac0c-b068-7d61-9a02-be05196701f5" xlink:to="loc_valn_GSKMember_019eac0c-b068-7a55-a4e4-5ccc9526b3ba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-b068-7994-8558-5513d248fe4f" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-b068-7c0b-b6ca-a15853f8c313" xlink:to="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-b068-7994-8558-5513d248fe4f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-b068-7994-8558-5513d248fe4f_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-b068-7994-8558-5513d248fe4f" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-b068-7994-8558-5513d248fe4f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-b068-79d6-bdcc-433796fc161a" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019eac0c-b068-7994-8558-5513d248fe4f" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-b068-79d6-bdcc-433796fc161a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_LymeVLA15Member_019eac0c-b068-72bc-9457-e367302b7f61" xlink:href="valn-20260630.xsd#valn_LymeVLA15Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019eac0c-b068-79d6-bdcc-433796fc161a" xlink:to="loc_valn_LymeVLA15Member_019eac0c-b068-72bc-9457-e367302b7f61" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_TypesOfContractsAxis_019eac0c-b068-7f11-8a98-9aac3e7d9c37" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_TypesOfContractsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-b068-7c0b-b6ca-a15853f8c313" xlink:to="loc_ifrs-full_TypesOfContractsAxis_019eac0c-b068-7f11-8a98-9aac3e7d9c37" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_TypesOfContractsDomain_019eac0c-b068-7f11-8a98-9aac3e7d9c37_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_TypesOfContractsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_TypesOfContractsAxis_019eac0c-b068-7f11-8a98-9aac3e7d9c37" xlink:to="loc_ifrs-full_TypesOfContractsDomain_019eac0c-b068-7f11-8a98-9aac3e7d9c37_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_TypesOfContractsDomain_019eac0c-b068-7c82-b14b-efa2b42cffaf" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_TypesOfContractsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_TypesOfContractsAxis_019eac0c-b068-7f11-8a98-9aac3e7d9c37" xlink:to="loc_ifrs-full_TypesOfContractsDomain_019eac0c-b068-7c82-b14b-efa2b42cffaf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_AmendedCollaborationAndLicenseAgreementMember_019eac0c-b068-7e66-92ad-acb2925e3cc7" xlink:href="valn-20260630.xsd#valn_AmendedCollaborationAndLicenseAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_TypesOfContractsDomain_019eac0c-b068-7c82-b14b-efa2b42cffaf" xlink:to="loc_valn_AmendedCollaborationAndLicenseAgreementMember_019eac0c-b068-7e66-92ad-acb2925e3cc7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_SupplyAgreementMember_019eac0c-b068-7f4c-941b-46ec897c88e8" xlink:href="valn-20260630.xsd#valn_SupplyAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_TypesOfContractsDomain_019eac0c-b068-7c82-b14b-efa2b42cffaf" xlink:to="loc_valn_SupplyAgreementMember_019eac0c-b068-7f4c-941b-46ec897c88e8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfProvisionsAxis_019eac0c-b068-7c30-9eed-b056430d28ad" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfProvisionsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersTable_019eac0c-b068-7c0b-b6ca-a15853f8c313" xlink:to="loc_ifrs-full_ClassesOfProvisionsAxis_019eac0c-b068-7c30-9eed-b056430d28ad" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfOtherProvisionsDomain_019eac0c-b068-7c30-9eed-b056430d28ad_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfOtherProvisionsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ClassesOfProvisionsAxis_019eac0c-b068-7c30-9eed-b056430d28ad" xlink:to="loc_ifrs-full_ClassesOfOtherProvisionsDomain_019eac0c-b068-7c30-9eed-b056430d28ad_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfOtherProvisionsDomain_019eac0c-b068-7cfc-8737-974d82062a6c" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfOtherProvisionsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ClassesOfProvisionsAxis_019eac0c-b068-7c30-9eed-b056430d28ad" xlink:to="loc_ifrs-full_ClassesOfOtherProvisionsDomain_019eac0c-b068-7cfc-8737-974d82062a6c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ReturnProvisionAndRebatesMember_019eac0c-b068-7550-8265-f8395ecff8a0" xlink:href="valn-20260630.xsd#valn_ReturnProvisionAndRebatesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfOtherProvisionsDomain_019eac0c-b068-7cfc-8737-974d82062a6c" xlink:to="loc_valn_ReturnProvisionAndRebatesMember_019eac0c-b068-7550-8265-f8395ecff8a0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_RefundsProvision_019eac0c-b068-76d9-b381-a45f691b72b8" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_RefundsProvision"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-b068-7b01-ba36-cbc18f1a9c7b" xlink:to="loc_ifrs-full_RefundsProvision_019eac0c-b068-76d9-b381-a45f691b72b8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CurrentRefundsProvision_019eac0c-b068-71be-a44d-38eda2d437f5" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CurrentRefundsProvision"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-b068-7b01-ba36-cbc18f1a9c7b" xlink:to="loc_ifrs-full_CurrentRefundsProvision_019eac0c-b068-71be-a44d-38eda2d437f5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_AdditionsRefundLiability_019eac0c-b068-70ae-8ecb-7d0173e8803e" xlink:href="valn-20260630.xsd#valn_AdditionsRefundLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-b068-7b01-ba36-cbc18f1a9c7b" xlink:to="loc_valn_AdditionsRefundLiability_019eac0c-b068-70ae-8ecb-7d0173e8803e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_NoncurrentRefundsProvision_019eac0c-b068-7cb3-85e0-0d8c593526cb" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_NoncurrentRefundsProvision"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfDisaggregationOfRevenueFromContractsWithCustomersLineItems_019eac0c-b068-7b01-ba36-cbc18f1a9c7b" xlink:to="loc_ifrs-full_NoncurrentRefundsProvision_019eac0c-b068-7cb3-85e0-0d8c593526cb" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/ProvisionsNarrativeDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#ProvisionsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/ProvisionsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfOtherProvisionsLineItems_019fae7d-9f15-7443-a0ab-6f73fc8a0b21" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfOtherProvisionsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfOtherProvisionsTable_019fae7d-9f15-7fe0-87dc-04d73c63a496" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfOtherProvisionsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfOtherProvisionsLineItems_019fae7d-9f15-7443-a0ab-6f73fc8a0b21" xlink:to="loc_ifrs-full_DisclosureOfOtherProvisionsTable_019fae7d-9f15-7fe0-87dc-04d73c63a496" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfProvisionsAxis_019fae7d-9f15-7d9b-9ccc-5b9deb579ed3" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfProvisionsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfOtherProvisionsTable_019fae7d-9f15-7fe0-87dc-04d73c63a496" xlink:to="loc_ifrs-full_ClassesOfProvisionsAxis_019fae7d-9f15-7d9b-9ccc-5b9deb579ed3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfOtherProvisionsDomain_019fae7d-9f15-7d9b-9ccc-5b9deb579ed3_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfOtherProvisionsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ClassesOfProvisionsAxis_019fae7d-9f15-7d9b-9ccc-5b9deb579ed3" xlink:to="loc_ifrs-full_ClassesOfOtherProvisionsDomain_019fae7d-9f15-7d9b-9ccc-5b9deb579ed3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ClassesOfOtherProvisionsDomain_019fae7d-9f15-724b-b957-8651bd49453c" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ClassesOfOtherProvisionsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ClassesOfProvisionsAxis_019fae7d-9f15-7d9b-9ccc-5b9deb579ed3" xlink:to="loc_ifrs-full_ClassesOfOtherProvisionsDomain_019fae7d-9f15-724b-b957-8651bd49453c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_LegalProceedingsProvisionMember_019fae7d-9f15-724d-8d24-71ee0e7de18f" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_LegalProceedingsProvisionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfOtherProvisionsDomain_019fae7d-9f15-724b-b957-8651bd49453c" xlink:to="loc_ifrs-full_LegalProceedingsProvisionMember_019fae7d-9f15-724d-8d24-71ee0e7de18f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OnerousContractsProvisionMember_019fae80-bccf-7aa3-ab12-150e883e9d0d" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_OnerousContractsProvisionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfOtherProvisionsDomain_019fae7d-9f15-724b-b957-8651bd49453c" xlink:to="loc_ifrs-full_OnerousContractsProvisionMember_019fae80-bccf-7aa3-ab12-150e883e9d0d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_MiscellaneousOtherProvisionsMember_019fd1ff-68ba-7445-b078-bdb70b3e4bad" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_MiscellaneousOtherProvisionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfOtherProvisionsDomain_019fae7d-9f15-724b-b957-8651bd49453c" xlink:to="loc_ifrs-full_MiscellaneousOtherProvisionsMember_019fd1ff-68ba-7445-b078-bdb70b3e4bad" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesAxis_019fae81-8ace-75a3-86c9-cee666abf413" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfOtherProvisionsTable_019fae7d-9f15-7fe0-87dc-04d73c63a496" xlink:to="loc_ifrs-full_ProductsAndServicesAxis_019fae81-8ace-75a3-86c9-cee666abf413" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019fae81-8ace-75a3-86c9-cee666abf413_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019fae81-8ace-75a3-86c9-cee666abf413" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019fae81-8ace-75a3-86c9-cee666abf413_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_ProductsAndServicesDomain_019fae81-8ace-7c85-9b0b-93c8c1d76efb" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ProductsAndServicesAxis_019fae81-8ace-75a3-86c9-cee666abf413" xlink:to="loc_ifrs-full_ProductsAndServicesDomain_019fae81-8ace-7c85-9b0b-93c8c1d76efb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_IXCHIQMember_019fae81-8ace-781b-b7fe-b435a58652c1" xlink:href="valn-20260630.xsd#valn_IXCHIQMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ProductsAndServicesDomain_019fae81-8ace-7c85-9b0b-93c8c1d76efb" xlink:to="loc_valn_IXCHIQMember_019fae81-8ace-781b-b7fe-b435a58652c1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OtherProvisions_019fae7d-9f15-74b4-885f-9a6ff3caf43a" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_OtherProvisions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfOtherProvisionsLineItems_019fae7d-9f15-7443-a0ab-6f73fc8a0b21" xlink:to="loc_ifrs-full_OtherProvisions_019fae7d-9f15-74b4-885f-9a6ff3caf43a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_AdditionalProvisionsOtherProvisions_019fae7d-9f15-73fe-a1bb-90a39559ee93" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_AdditionalProvisionsOtherProvisions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfOtherProvisionsLineItems_019fae7d-9f15-7443-a0ab-6f73fc8a0b21" xlink:to="loc_ifrs-full_AdditionalProvisionsOtherProvisions_019fae7d-9f15-73fe-a1bb-90a39559ee93" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://valneva.com/role/RelatedpartytransactionsDetails" xlink:type="simple" xlink:href="valn-20260630.xsd#RelatedpartytransactionsDetails"/>
  <link:definitionLink xlink:role="http://valneva.com/role/RelatedpartytransactionsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_019eac0c-b068-7990-b64c-f69be8ef2f90" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesTable_019eac0c-b068-7dbc-837f-9d1ec25e2529" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_019eac0c-b068-7990-b64c-f69be8ef2f90" xlink:to="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesTable_019eac0c-b068-7dbc-837f-9d1ec25e2529" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_BorrowingsByNameAxis_019eac0c-b068-7649-b5bd-473979038bca" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_BorrowingsByNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesTable_019eac0c-b068-7dbc-837f-9d1ec25e2529" xlink:to="loc_ifrs-full_BorrowingsByNameAxis_019eac0c-b068-7649-b5bd-473979038bca" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_BorrowingsByNameDomain_019eac0c-b068-7649-b5bd-473979038bca_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_BorrowingsByNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_BorrowingsByNameAxis_019eac0c-b068-7649-b5bd-473979038bca" xlink:to="loc_ifrs-full_BorrowingsByNameDomain_019eac0c-b068-7649-b5bd-473979038bca_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_BorrowingsByNameDomain_019eac0c-b068-72a0-b241-2f7c30dd9c7f" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_BorrowingsByNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_BorrowingsByNameAxis_019eac0c-b068-7649-b5bd-473979038bca" xlink:to="loc_ifrs-full_BorrowingsByNameDomain_019eac0c-b068-72a0-b241-2f7c30dd9c7f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_ResearchTaxCreditMember_019eac0c-b068-7d4f-b6f9-5f3d6fec1189" xlink:href="valn-20260630.xsd#valn_ResearchTaxCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_BorrowingsByNameDomain_019eac0c-b068-72a0-b241-2f7c30dd9c7f" xlink:to="loc_valn_ResearchTaxCreditMember_019eac0c-b068-7d4f-b6f9-5f3d6fec1189" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CounterpartiesAxis_019eac0c-b068-7d50-8c2d-1c7a3dd25bfb" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CounterpartiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesTable_019eac0c-b068-7dbc-837f-9d1ec25e2529" xlink:to="loc_ifrs-full_CounterpartiesAxis_019eac0c-b068-7d50-8c2d-1c7a3dd25bfb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CounterpartiesDomain_019eac0c-b068-7d50-8c2d-1c7a3dd25bfb_default" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CounterpartiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_CounterpartiesAxis_019eac0c-b068-7d50-8c2d-1c7a3dd25bfb" xlink:to="loc_ifrs-full_CounterpartiesDomain_019eac0c-b068-7d50-8c2d-1c7a3dd25bfb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CounterpartiesDomain_019eac0c-b068-71b4-8aa8-eb26dfbe6b9c" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_CounterpartiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_CounterpartiesAxis_019eac0c-b068-7d50-8c2d-1c7a3dd25bfb" xlink:to="loc_ifrs-full_CounterpartiesDomain_019eac0c-b068-71b4-8aa8-eb26dfbe6b9c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_BPIFranceMember_019eac0c-b068-7d2e-80bc-50d6148fe384" xlink:href="valn-20260630.xsd#valn_BPIFranceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_CounterpartiesDomain_019eac0c-b068-71b4-8aa8-eb26dfbe6b9c" xlink:to="loc_valn_BPIFranceMember_019eac0c-b068-7d2e-80bc-50d6148fe384" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_valn_BorrowingsGrantedPercentageOfReceivables_019eac0c-b068-7008-8de3-4f34fb10440d" xlink:href="valn-20260630.xsd#valn_BorrowingsGrantedPercentageOfReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_019eac0c-b068-7990-b64c-f69be8ef2f90" xlink:to="loc_valn_BorrowingsGrantedPercentageOfReceivables_019eac0c-b068-7008-8de3-4f34fb10440d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_Borrowings_019eac0c-b068-7e9e-af92-576c68c65020" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_Borrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_019eac0c-b068-7990-b64c-f69be8ef2f90" xlink:to="loc_ifrs-full_Borrowings_019eac0c-b068-7e9e-af92-576c68c65020" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_KeyManagementPersonnelCompensation_019eac0c-b068-7ba4-99cd-281ee986ff59" xlink:href="https://xbrl.ifrs.org/taxonomy/2025-03-27/full_ifrs/full_ifrs-cor_2025-03-27.xsd#ifrs-full_KeyManagementPersonnelCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_019eac0c-b068-7990-b64c-f69be8ef2f90" xlink:to="loc_ifrs-full_KeyManagementPersonnelCompensation_019eac0c-b068-7ba4-99cd-281ee986ff59" xlink:type="arc" order="2"/>
  </link:definitionLink>
</link:linkbase>
