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<!--Created by 2H Software, Powered by IRIS Carbon, Unique Code 6acfff7ae318120bc2e29509, Generated At Wed, 14 Oct 2026 22:18:20 GMT-->
<xsd:schema xmlns:dtr-types="http://www.xbrl.org/dtr/type/2022-03-31" xmlns:us-roles="http://fasb.org/us-roles/2025" xmlns:dei="http://xbrl.sec.gov/dei/2025" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:ref="http://www.xbrl.org/2006/ref" xmlns:negated="http://www.xbrl.org/2009/role/negated" xmlns:num="http://www.xbrl.org/dtr/type/numeric" xmlns:nonnum="http://www.xbrl.org/dtr/type/non-numeric" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xl="http://www.xbrl.org/2003/XLink" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:csan="http://www.cosan.com/20251231" elementFormDefault="qualified" attributeFormDefault="unqualified" targetNamespace="http://www.cosan.com/20251231">
  <xsd:annotation>
    <xsd:appinfo>
      <link:linkbaseRef xlink:type="simple" xlink:href="csan-20251231_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="csan-20251231_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="csan-20251231_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="csan-20251231_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:roleType roleURI="http://www.cosan.com/role/CoverPage" id="CoverPage">
        <link:definition>1001 - Document - Cover Page</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
    </xsd:appinfo>
  </xsd:annotation>
  <xsd:import namespace="http://www.xbrl.org/dtr/type/2022-03-31" schemaLocation="https://www.xbrl.org/dtr/type/2022-03-31/types.xsd" />
  <xsd:import namespace="http://fasb.org/us-roles/2025" schemaLocation="https://xbrl.fasb.org/us-gaap/2025/elts/us-roles-2025.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/dei/2025" schemaLocation="https://xbrl.sec.gov/dei/2025/dei-2025.xsd" />
  <xsd:import namespace="http://www.w3.org/1999/xlink" schemaLocation="http://www.xbrl.org/2003/xlink-2003-12-31.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2003/XLink" schemaLocation="http://www.xbrl.org/2003/xl-2003-12-31.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd" />
  <xsd:import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2006/ref" schemaLocation="http://www.xbrl.org/2006/ref-2006-02-27.xsd" />
  <xsd:element name="CommonSharesMember" id="csan_CommonSharesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xsd:element name="AmericanDepositoryReceiptMember" id="csan_AmericanDepositoryReceiptMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
</xsd:schema>
