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

    <schemaVersion>X0603</schemaVersion>

    <submissionType>D</submissionType>

    <testOrLive>LIVE</testOrLive>

    <primaryIssuer>
        <cik>0000897075</cik>
        <entityName>REPROS THERAPEUTICS INC.</entityName>
        <issuerAddress>
            <street1>2408 Timberloch Place</street1>
            <street2>Suite B-7</street2>
            <city>The Woodlands</city>
            <stateOrCountry>TX</stateOrCountry>
            <zipCode>77380</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>281-719-3400</issuerPhoneNumber>
        <jurisdictionOfInc>DELAWARE</jurisdictionOfInc>
        <issuerPreviousNameList>
            <previousName>Zonagen, Inc.</previousName>
        </issuerPreviousNameList>
        <edgarPreviousNameList>
            <previousName>REPROS THERAPEUTICS INC</previousName>
            <previousName>ZONAGEN INC</previousName>
        </edgarPreviousNameList>
        <entityType>Corporation</entityType>
        <yearOfInc>
            <overFiveYears>true</overFiveYears>
        </yearOfInc>
    </primaryIssuer>

    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Joseph</firstName>
                <middleName>S.</middleName>
                <lastName>Podolski</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>2408 Timberloch Place, B-7</street1>
                <city>The Woodlands</city>
                <stateOrCountry>TX</stateOrCountry>
                <zipCode>77380</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Katherine</firstName>
                <lastName>Anderson</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>2408 Timberloch Place, B-7</street1>
                <city>The Woodlands</city>
                <stateOrCountry>TX</stateOrCountry>
                <zipCode>77380</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Mark</firstName>
                <lastName>Lappe</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>2408 Timberloch Place, B-7</street1>
                <city>The Woodlands</city>
                <stateOrCountry>TX</stateOrCountry>
                <zipCode>77380</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Daniel</firstName>
                <middleName>F.</middleName>
                <lastName>Cain</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>2408 Timberloch Place, B-7</street1>
                <city>The Woodlands</city>
                <stateOrCountry>TX</stateOrCountry>
                <zipCode>77380</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Jean</firstName>
                <middleName>L.</middleName>
                <lastName>Fourcroy</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>2408 Timberloch Place, B-7</street1>
                <city>The Woodlands</city>
                <stateOrCountry>TX</stateOrCountry>
                <zipCode>77380</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Nola</firstName>
                <lastName>Masterson</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>2408 Timberloch Place, B-7</street1>
                <city>The Woodlands</city>
                <stateOrCountry>TX</stateOrCountry>
                <zipCode>77380</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
    </relatedPersonsList>

    <offeringData>
        <industryGroup>
            <industryGroupType>Biotechnology</industryGroupType>
        </industryGroup>
        <issuerSize>
            <revenueRange>$1 - $1,000,000</revenueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>06</item>
        </federalExemptionsExclusions>
        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>false</isAmendment>
            </newOrAmendment>
            <dateOfFirstSale>
                <value>2009-10-29</value>
            </dateOfFirstSale>
        </typeOfFiling>
        <durationOfOffering>
            <moreThanOneYear>false</moreThanOneYear>
        </durationOfOffering>
        <typesOfSecuritiesOffered>
            <isEquityType>true</isEquityType>
        </typesOfSecuritiesOffered>
        <businessCombinationTransaction>
            <isBusinessCombinationTransaction>false</isBusinessCombinationTransaction>
            <clarificationOfResponse></clarificationOfResponse>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>0</minimumInvestmentAccepted>
        <salesCompensationList></salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>6054227</totalOfferingAmount>
            <totalAmountSold>5897313</totalAmountSold>
            <totalRemaining>156914</totalRemaining>
            <clarificationOfResponse></clarificationOfResponse>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>true</hasNonAccreditedInvestors>
            <numberNonAccreditedInvestors>2</numberNonAccreditedInvestors>
            <totalNumberAlreadyInvested>9</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
            <salesCommissions>
                <dollarAmount>0</dollarAmount>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
            </findersFees>
            <clarificationOfResponse></clarificationOfResponse>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>0</dollarAmount>
                <isEstimate>true</isEstimate>
            </grossProceedsUsed>
            <clarificationOfResponse></clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>true</authorizedRepresentative>
            <signature>
                <issuerName>REPROS THERAPEUTICS INC.</issuerName>
                <signatureName>Joseph S. Podolski</signatureName>
                <nameOfSigner>Joseph S. Podolski</nameOfSigner>
                <signatureTitle>Chief Executive Officer</signatureTitle>
                <signatureDate>2009-11-11</signatureDate>
            </signature>
        </signatureBlock>
    </offeringData>
</edgarSubmission>
