<?xml version="1.0" encoding="UTF-8"?>
<edgarSubmission xmlns="http://www.sec.gov/edgar/seventeenafiler" xmlns:com="http://www.sec.gov/edgar/common">
  <headerData>
    <submissionType>X-17A-5</submissionType>
    <filerInfo>
      <filer>
        <filerCredentials>
          <filerCik>0000081567</filerCik>
          <filerCcc>XXXXXXXX</filerCcc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>
      <flags>
        <returnCopyFlag>true</returnCopyFlag>
        <confirmingCopyFlag>false</confirmingCopyFlag>
        <overrideInternetFlag>false</overrideInternetFlag>
      </flags>
    </filerInfo>
  </headerData>
  <formData>
    <submissionInformation>
      <periodBegin>01-01-2025</periodBegin>
      <periodEnd>12-31-2025</periodEnd>
      <typeOfRegistrant>
        <typeOfBDRegistrant>Broker-dealer</typeOfBDRegistrant>
      </typeOfRegistrant>
      <materialWeakness>N</materialWeakness>
    </submissionInformation>
    <registrantIdentification>
      <brokerDealerName>A.G. QUINTAL INVESTMENT COMPANY INC.</brokerDealerName>
      <businessAddress>
        <com:street1>2177 ACUSHNET AVE.</com:street1>
        <com:city>NEW BEDFORD</com:city>
        <com:stateOrCountry>MA</com:stateOrCountry>
        <com:zipCode>02745-6316</com:zipCode>
      </businessAddress>
      <contactPersonName>Mark A Quintal</contactPersonName>
      <contactPersonPhoneNumber>508-995-2611</contactPersonPhoneNumber>
    </registrantIdentification>
    <accountantIdentification>
      <accountantName>Fulvio and Associates, LLP</accountantName>
      <accountantAddress>
        <com:street1>5 West 37th Street, 4th Floor</com:street1>
        <com:city>New York</com:city>
        <com:stateOrCountry>NY</com:stateOrCountry>
        <com:zipCode>10018</com:zipCode>
      </accountantAddress>
      <accountantType>Certified Public Accountant</accountantType>
    </accountantIdentification>
    <oathSignature>
      <signPersonName>Mark A. Quintal</signPersonName>
      <entityName>A.G. QUINTAL INVESTMENT COMPANY INC.</entityName>
      <signDate>03-02-2026</signDate>
      <signature>Mark A Quintal</signature>
      <oathTitle>President</oathTitle>
      <confirmNotarizedFlag>Y</confirmNotarizedFlag>
    </oathSignature>
  </formData>
</edgarSubmission>
