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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-04-26</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001060021</issuerCik>
        <issuerName>BLACKROCK INC /NY</issuerName>
        <issuerTradingSymbol>BLK</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001059242</rptOwnerCik>
            <rptOwnerName>GOLUB BENNETT</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>BLACKROCK, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>40 EAST 52ND STREET</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10022</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Head of Portfolio Risk Mgmnt</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Shares of Class A Common Stock (par value $0.01 per share)</value>
            </securityTitle>
            <transactionDate>
                <value>2006-04-26</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>6666</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>228193</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Shares of Class A Common Stock (par value $0.01 per share)</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>18741.0659</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By family trust</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Shares of Class A Common Stock (par value $0.01 per share)</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>18741.0659</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By family trust</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Shares of Class A Common Stock (par value $0.01 per share)</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>18741.0659</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By family trust</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Includes 1,284 shares of Class A Common Stock acquired by the reporting person through March 31, 2006 under The PNC Financial Services Group, Inc. Incentive Savings Plan (the &quot;ISP&quot;).  The information on this report with respect to the ISP is based on a plan statement dated as of March 31, 2006. Also includes 2,525 shares of Class A Common Stock acquired under the BlackRock, Inc. Employee Stock Purchase Plan through January 31, 2006.  Also includes 2,360 shares of Class A Common Stock granted under the BlackRock, Inc. 1999 Stock Award and Incentive Plan as restricted shares and which are now fully vested.  Also includes 5,369 shares of restricted Class A Common Stock granted under the BlackRock, Inc. 1999 Stock Award and Incentive Plan, vesting in two equal installments on 12/15/06 and 12/15/07.</footnote>
        <footnote id="F2">Also includes 5,961 Restricted Stock Units granted under the BlackRock, Inc. 1999 Stock Award and Incentive Plan.  Each Restricted Stock Unit is payable solely by delivery of an equal number of shares of Class A Common Stock and vests in three equal installments on 1/31/07, 1/31/08 and 1/31/09.</footnote>
        <footnote id="F3">These shares are held in a trust for the benefit of one of the reporting person?s children. The reporting person and the reporting person?s spouse are trustees of the trust. The reporting person disclaims beneficial ownership of these securities, and the filing of this report is not an admission that the reporting person is the beneficial owner of these securities for purposes of Section 16 or for any other purpose.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Daniel R. Waltcher as Attorney-in-Fact for Bennet W. Golub</signatureName>
        <signatureDate>2006-04-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
