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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-12-15</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001215403</rptOwnerCik>
            <rptOwnerName>PAULSEN WILLIAM F</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CRYSTAL RIVER CAPITAL, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>THREE WORLD FIMANCIAL CENTER, 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>2006-12-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>497</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3127</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 stcok (&quot;Common Stock&quot;) of Crytsal River Capital, Inc. (the &quot;Isuer&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 diretor of the Issuer.</footnote>
        <footnote id="F2">Represents deferred sock 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 paid by the Issuer on December 15, 2006 by (2) the closing price of the Common Stock on the New York Stock Exchange on December 15, 2006.</footnote>
        <footnote id="F3">Excludes 10,000 shares of Common Sock owned by the The Paulsen Foundation, for which the Reporting Person serves as president and in which the Reporting Persson has no pecuniary interest. Excludes 3,334 RSUs awarded pursuant to the Plan that vest over time and are settled in Issuer's deferred stock units upon vesting, which deferred stock units are to be settled in Issuer's Common Stock on a one-for-one basis that is issued on the date on which the Reporting Person ceases to be a director of the Issuer. 1,334 of such RSUs vest in equal installments on March 15, 2007 and March 15, 2008. 2,000 of such RSUs vest on November 9, 2007, the first anniversary of the date of grant.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ John J. Feeney, Jr., on behalf of Walliam F. Paulsen</signatureName>
        <signatureDate>2006-12-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
