<?xml version="1.0"?>
<edgarSubmission>

    <schemaVersion>X0704</schemaVersion>

    <submissionType>D</submissionType>

    <testOrLive>LIVE</testOrLive>

    <primaryIssuer>
        <cik>0001499830</cik>
        <entityName>Duo Security, Inc.</entityName>
        <issuerAddress>
            <street1>1327 JONES DR.</street1>
            <street2>SUITE 106</street2>
            <city>ANN ARBOR</city>
            <stateOrCountry>MI</stateOrCountry>
            <stateOrCountryDescription>MICHIGAN</stateOrCountryDescription>
            <zipCode>48105</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>855-386-2884</issuerPhoneNumber>
        <jurisdictionOfInc>DELAWARE</jurisdictionOfInc>
        <edgarPreviousNameList>
            <previousName>Scio Security, Inc.</previousName>
        </edgarPreviousNameList>
        <entityType>Corporation</entityType>
        <yearOfInc>
            <withinFiveYears>true</withinFiveYears>
            <value>2009</value>
        </yearOfInc>
    </primaryIssuer>

    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Douglas</firstName>
                <middleName>Joon</middleName>
                <lastName>Song</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>1327 Jones Dr.</street1>
                <street2>Ste. 106</street2>
                <city>Ann Arbor</city>
                <stateOrCountry>MI</stateOrCountry>
                <stateOrCountryDescription>MICHIGAN</stateOrCountryDescription>
                <zipCode>48105</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Jonathan</firstName>
                <middleName>Clarke</middleName>
                <lastName>Oberheide</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>1327 Jones Dr.</street1>
                <street2>Ste. 106</street2>
                <city>Ann Arbor</city>
                <stateOrCountry>MI</stateOrCountry>
                <stateOrCountryDescription>MICHIGAN</stateOrCountryDescription>
                <zipCode>48105</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
    </relatedPersonsList>

    <offeringData>
        <industryGroup>
            <industryGroupType>Other Technology</industryGroupType>
        </industryGroup>
        <issuerSize>
            <revenueRange>$1 - $1,000,000</revenueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>06</item>
        </federalExemptionsExclusions>
        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>false</isAmendment>
            </newOrAmendment>
            <dateOfFirstSale>
                <value>2012-02-17</value>
            </dateOfFirstSale>
        </typeOfFiling>
        <durationOfOffering>
            <moreThanOneYear>false</moreThanOneYear>
        </durationOfOffering>
        <typesOfSecuritiesOffered>
            <isEquityType>true</isEquityType>
        </typesOfSecuritiesOffered>
        <businessCombinationTransaction>
            <isBusinessCombinationTransaction>false</isBusinessCombinationTransaction>
            <clarificationOfResponse></clarificationOfResponse>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>24998</minimumInvestmentAccepted>
        <salesCompensationList></salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>4999998</totalOfferingAmount>
            <totalAmountSold>4999998</totalAmountSold>
            <totalRemaining>0</totalRemaining>
            <clarificationOfResponse></clarificationOfResponse>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>5</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
            <salesCommissions>
                <dollarAmount>0</dollarAmount>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
            </findersFees>
            <clarificationOfResponse></clarificationOfResponse>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>225000</dollarAmount>
                <isEstimate>true</isEstimate>
            </grossProceedsUsed>
            <clarificationOfResponse>Salary for 2012</clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>Duo Security, Inc.</issuerName>
                <signatureName>Matthew W. Bower</signatureName>
                <nameOfSigner>Matthew W. Bower</nameOfSigner>
                <signatureTitle>Authorized Agent</signatureTitle>
                <signatureDate>2012-02-22</signatureDate>
            </signature>
        </signatureBlock>
    </offeringData>
</edgarSubmission>
