<?xml version="1.0" encoding="US-ASCII"?>
<!-- Generated by Broadridge Transform (tm) - http://www.broadridge.com -->
<!-- Created: Wed Apr 22 20:05:32 UTC 2026 -->
<xs:schema elementFormDefault="qualified" xmlns:qlys="http://www.qualys.com/20260610" targetNamespace="http://www.qualys.com/20260610" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:us-types="http://xbrl.us/us-types/2009-01-31" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:dtr="http://www.xbrl.org/dtr/type/2024-01-31" xmlns:xbrli="http://www.xbrl.org/2003/instance">
  <xs:annotation>
    <xs:appinfo>
      <link:linkbaseRef xlink:type="simple" xlink:href="qlys-20260610_lab.xml" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef"/>
      <link:linkbaseRef xlink:type="simple" xlink:href="qlys-20260610_pre.xml" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef"/>
      <link:linkbaseRef xlink:type="simple" xlink:href="qlys-20260610_def.xml" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef"/>
      <link:roleType roleURI="http://www.qualys.com/role/AdditionalDimensions" id="qlys_r_AdditionalDimensions">
        <link:definition>999000 - Disclosure - Pay vs Performance Disclosure - Additional Dimensions</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
    </xs:appinfo>
  </xs:annotation>
  <xs:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd"/>
  <xs:import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd"/>
  <xs:import namespace="http://xbrl.sec.gov/ecd/2025" schemaLocation="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd"/>
  <xs:import namespace="http://xbrl.sec.gov/dei/2025" schemaLocation="https://xbrl.sec.gov/dei/2025/dei-2025.xsd"/>
  <xs:import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd"/>
  <xs:import namespace="http://www.xbrl.org/dtr/type/2024-01-31" schemaLocation="https://www.xbrl.org/dtr/type/2024-01-31/types.xsd"/>
  <xs:import namespace="http://xbrl.sec.gov/ecd-sub/2025" schemaLocation="https://xbrl.sec.gov/ecd/2025/ecd-sub-2025.xsd"/>
  <xs:import namespace="http://xbrl.sec.gov/dei-sub/2025" schemaLocation="https://xbrl.sec.gov/dei/2025/dei-sub-2025.xsd"/>
  <xs:import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd"/>
  <xs:element name="PhilippeFCourtotMember" type="dtr:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="qlys_PhilippeFCourtotMember"/>
<!-- [WMV7][bTWPo9emgPWL3Lmp9nHimHN9o6VntgB1Z9LeJnzC6WojUnCKLE+BLw1kUF50+YU1OZtlsPu3fZrzai9zVmQgHKJK2Bj2jRo/Affcc4eEWSgDevO82SEHifggYLxiEWhPY/59tqB3a3/gWzXtov+/nkuOaMJTExP9yui96dDHbYfZZ2fzpGeqzz2gb8Qeo/9ToCn6MVjpbTAbcHC4JZCN+8sVw1MHPng9EO9ar0twRLgo/OThM/wxJZAPt8qkp6pcUQPdPJMC+q6hTGB5u57cRzX5W/IaOxN3DpAf1VzikYZdTe18M0m99zw9g5EOA5HGFi/xhiPIlXrCPYrFvcLUI9++uLcak79SCFz7qLY=] CSR-->
  <xs:element name="SumedhSThakarMember" type="dtr:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="qlys_SumedhSThakarMember"/>
</xs:schema>
