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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-07-30</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001294561</rptOwnerCik>
            <rptOwnerName>Salvatore Louis P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CRYSTAL RIVER CAPITAL, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>3 WFC, 200 VESEY STREET, 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>2010-07-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>1</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>209723</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-07-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </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, pursuant to the terms of the Merger Agreement (as defined below), received the Merger Consideration (as defined below) on the Closing Date (as defined below) in exchange for such deferred stock units.</footnote>
        <footnote id="F2">On February 23, 2010, Crystal River Capital, Inc. (&quot;Crystal&quot;) and Brookfield Asset Management Inc. (&quot;Brookfield&quot;) entered into a merger agreement (the &quot;Merger Agreement&quot;), which provided for a merger in which Crystal would become a wholly-owned subsidiary of Brookfield (the &quot;Merger&quot;). The Merger became effective on July 30, 2010 (the &quot;Closing Date&quot;). At the effective time of the Merger, each outstanding share of Crystal common stock (other than treasury shares held by Crystal and shares held by wholly-owned subsidiaries of Brookfield) converted into the right to receive $0.60 in cash.</footnote>
        <footnote id="F3">On February 23, 2010, Crystal and Brookfield entered into the Merger Agreement, which provided for a merger in which Crystal would become a wholly-owned subsidiary of Brookfield. The Merger became effective on July 30, 2010. At the effective time of the Merger, each outstanding share of Crystal common stock (other than the treasury shares held by Crystal and shares held by by wholly-owned subsidiaries of Brookfield) converted into the right to receive $0.60 in cash.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Louis P. Salvatore</signatureName>
        <signatureDate>2010-08-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
