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

    <schemaVersion>X0203</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2010-01-01</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000921847</issuerCik>
        <issuerName>HUDSON CITY BANCORP INC</issuerName>
        <issuerTradingSymbol>HCBK</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001479452</rptOwnerCik>
            <rptOwnerName>Mahler Christopher L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>WEST 80 CENTURY ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PARAMUS</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07652</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, par value $0.01 per share</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>269144</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, par value $0.01 per share</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>80885</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By PIB</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, par value $0.01 per share</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>32214</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By ESOP</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, par value $0.01 per share</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2244</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>12.76</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2016-07-20</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>100000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>12.22</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2014-02-18</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>64120</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>12.76</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2009-01-20</value>
            </exerciseDate>
            <expirationDate>
                <value>2016-07-20</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>50000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>11.91</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2005-01-13</value>
            </exerciseDate>
            <expirationDate>
                <value>2014-01-21</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>32059</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Award to the reporting person of 3,500 shares of common stock pursuant to the Hudson City Bancorp, Inc. 2000 Recognition and Retention Plan (&quot;RRP&quot;), which the stockholders approved at a Special Meeting of Stockholders of Hudson City Bancorp, Inc. held on January 13, 2000 (&quot;Special Meeting&quot;), effective February 19, 2004.  The shares awarded were adjusted to reflect a 3.206-for-1 stock split on June 7, 2005 and 2,244 shares vested and became directly owned by the reporting person on each of April 20, 2006, 2007 and 2008. 2,245 shares vested and became directly owned by the reporting person on April 20, 2009.  The remaining 2,244 shares will vest and become directly owned by the reporting person on April 20, 2010.</footnote>
        <footnote id="F2">Grant to the reporting person of options to buy 100,000 shares of common stock pursuant to the Hudson City Bancorp, Inc. 2006 Stock Incentive Plan, which the stockholders approved at the Annual Meeting of Stockholders of Hudson City Bancorp, Inc. held on June 8, 2006, effective July 21, 2006.  60,000 of such options vested and became exercisable on July 21, 2009. The remaining 40,000 options will vest and become exercisable on July 21, 2011.</footnote>
        <footnote id="F3">Grant to the reporting person of options to buy 20,000 shares of common stock, pursuant to the Hudson City Bancorp, Inc. 2000 Stock Option Plan that was approved by the stockholders at the Special Meeting, effective February 19, 2004.  The options awarded and the exercise price of those options were adjusted to reflect a 3.206-for-1 split on June 7, 2005 and 12,824 options vested and became exercisable on each of January 13, 2006, 2007, 2008 and 2009.  The remaining 12,824 options will vest and become exercisable on January 11, 2010.</footnote>
        <footnote id="F4">Shares are held in the reporting person's account in the Hudson City Savings Bank Profit Incentive Bonus Plan.</footnote>
    </footnotes>

    <remarks>On  1/23/09 the reporting person received a grant of Performance Stock Options to purchase 45,000 shares of common stock at a price per share of $12.03. These options have a 10-yr term ending 1/22/19 (or earlier in certain circumstances) &amp; become exercisable provided the reporting person remains in continuous service through such date &amp; certain corp. measures tied to return on equity &amp; diluted earnings per share are satisfied on or prior to 1/23/12. On 1/23/09 the reporting person received a Performance Retention Restricted Stock award of 15,000 shares of common stock. These shares will fully vest on 1/23/12 provided certain corp. performance measures tied to operating efficiency during the 2009 fiscal yr have been met. On 1/25/08, the reporting person received a grant of Performance Stock Options to purchase 50,000 shares of common stock at a price per share of $15.69.  These options have a 10-yr term ending 1/24/18 (or earlier in certain circumstances) &amp; become exercisable on 1/25/11, provided that the reporting person remains in continuous service through such date &amp; certain corp. performance measures tied to return on equity &amp; diluted earnings per share have been satisfied.  On 1/26/07, the reporting person received a grant of Performance Stock Options to purchase 45,000 shares of common stock at a price per share of $13.78.  These options have a 10-yr term ending 1/25/17 (or earlier in certain circumstances) &amp; become exercisable on 1/26/10 provided that the reporting person remains in continuous service through such date &amp; certain corp. performance measures tied to return on equity &amp; diluted earnings per share have been satisfied. Under applicable SEC regulations, this stock award &amp; these option grants are reportable in Tables I &amp; Il of Form 4, respectively, only if and when the performance conditions have been satisfied.    Exhibit List - Exhibit 24 (Power of Attorney)</remarks>

    <ownerSignature>
        <signatureName>Veronica A. Olszewski, Attorney-in-Fact</signatureName>
        <signatureDate>2010-01-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
