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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2011-04-28</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001342854</issuerCik>
        <issuerName>PARAMOUNT GOLD &amp; SILVER CORP.</issuerName>
        <issuerTradingSymbol>PZG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001499884</rptOwnerCik>
            <rptOwnerName>Kennedy Shawn Michael Thomas</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>895 GLOVER ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SMITHERS</rptOwnerCity>
            <rptOwnerState>A1</rptOwnerState>
            <rptOwnerZipCode>V0J2N6</rptOwnerZipCode>
            <rptOwnerStateDescription>BRITISH COLUMBIA, CANADA</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

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            <deemedExecutionDate></deemedExecutionDate>
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                <value>Common Stock</value>
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                <transactionAcquiredDisposedCode>
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                <transactionShares>
                    <value>10000</value>
                </transactionShares>
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                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
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                <value>Common Stock</value>
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                <value>Common Stock</value>
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                <value>Common Stock</value>
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            <transactionDate>
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    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Shawn Kennedy</signatureName>
        <signatureDate>2011-05-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
