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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-04-18</periodOfReport>

    <issuer>
        <issuerCik>0001330849</issuerCik>
        <issuerName>HERCULES OFFSHORE, INC.</issuerName>
        <issuerTradingSymbol>HERO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001342155</rptOwnerCik>
            <rptOwnerName>Hord Thomas E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>11 GREENWAY PLAZA, SUITE 2950</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77046</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP &amp; COO Hercules Drilling Co</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $0.01 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2006-04-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>33771</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>34.38</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>253122</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The reported securities were sold pursuant to an underwriting agreement dated April 11, 2006 among Hercules Offshore, Inc., certain selling stockholders (including the reporting person) and the underwriters named therein in connection with a public offering of 8,000,000 shares of common stock of Hercules Offshore, Inc.</footnote>
        <footnote id="F2">Equal to an initial price to the public of $36.00 per share less a $1.62 per share discount to the underwriters.</footnote>
        <footnote id="F3">Due to a mathematical error, the amount of securities beneficially owned was incorrectly reported in Mr. Hord's previous Form 4 (filed November 3, 2005) as 286,693 instead of 286,893.   The figure reported in Column 5 of Table I is based on the corrected number of shares.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>James Noe, attorney-in-fact</signatureName>
        <signatureDate>2006-04-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
