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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-06-09</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001344705</issuerCik>
        <issuerName>Crystal River Capital, Inc.</issuerName>
        <issuerTradingSymbol>CYRV</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001367312</rptOwnerCik>
            <rptOwnerName>HANSEN HARALD</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CRYSTAL RIVER CAPITAL, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>3 WORLD FIN CTR, 200 VESEY ST, 10TH FL</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10281</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2009-06-09</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2000</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Restricted stock units awarded pursuant to the Issuer's 2005 Long-Term Incentive Plan (the &quot;Plan&quot;) that vest over time and are to be settled in common stock (&quot;Common Stock&quot;) of Crystal River Capital, Inc. (the &quot;Issuer&quot;) on a one-for-one basis in one installment that is issued on the date on which the Reporting Person ceases to be a director of the Issuer. All 2,000 of such restricted stock units vest on June 9, 2010.</footnote>
        <footnote id="F2">Represents grant of restricted stock units pursuant to the Plan.</footnote>
        <footnote id="F3">Excludes 4,800 shares of Common Stock owned by the Reporting Person. Excludes 46,314 deferred stock units awarded pursuant to the Plan, which deferred stock units are to be settled in Issuer Common Stock on a one-for-one basis on the date on which the Reporting Person ceases to be a director of the Issuer.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ John J. Feeney, Jr., on behalf of Harald R. Hansen</signatureName>
        <signatureDate>2009-06-11</signatureDate>
    </ownerSignature>
</ownershipDocument>
