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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-11-10</periodOfReport>

    <issuer>
        <issuerCik>0001210677</issuerCik>
        <issuerName>FIRST ADVANTAGE CORP</issuerName>
        <issuerTradingSymbol>FADV</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001237462</rptOwnerCik>
            <rptOwnerName>ROBERT DON</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>100 CARILLON PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>ST. PETERSBURG</rptOwnerCity>
            <rptOwnerState>FL</rptOwnerState>
            <rptOwnerZipCode>33716</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-11-10</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>7944</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Shares of Class A common stock (&quot;Class A Shares&quot;) tendered to The First American Corporation (&quot;First American&quot;) pursuant to the previously announced registered exchange offer for the Class A Shares commenced on October 9, 2009 which expired on November 10, 2009.</footnote>
        <footnote id="F2">The consideration offered by First American in the exchange offer was 0.58 of a First American common share for each Class A Share, plus cash in lieu of any fractional share otherwise issuable to a holder of Class A Shares after aggregating all First Amerian common shares such holder was entitled to receive in the exchange offer.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Sharlyn Nudelman, Power of Attorney</signatureName>
        <signatureDate>2009-11-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
