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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-03-15</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001215403</rptOwnerCik>
            <rptOwnerName>PAULSEN WILLIAM F</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CRYSTAL RIVER CAPITAL, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>3 WFC, 200 VESEY STREET, 10TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10281-1010</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>2010-03-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>25410</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>167140</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Deferred stock units awarded pursuant to the Issuer's 2005 Long-Term Incentive Plan (the &quot;Plan&quot;) that 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.</footnote>
        <footnote id="F2">Represents deferred stock units credited to the account of the Reporting Person which convert to shares of Common Stock of the Issuer on a one-for-one basis. The number of shares of Common Stock subject to the deferred stock units credited to the Reporting Person was determined by dividing (1) the quarterly director's fee of $12,500 and the Compensation Committee Chair fee of $3,000 paid by the Issuer on March 15, 2010 by (2) the closing price of the Common Stock on the Over-the-Counter Market on March 15, 2010.</footnote>
        <footnote id="F3">Excludes 2,000 restricted stock units awarded pursuant to the Plan that vest over time and are settled in Issuer deferred stock units upon vesting, which deferred stock units are to be settled in Issuer Common Stock 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>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ William F. Paulsen</signatureName>
        <signatureDate>2010-03-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
