-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 Hny+ACheiULxCHx9uLuejBwxMHqLa0KPvCvu9hYUcOHf29vwWVOB6Vq14vxKXNXd
 +eOTOKbNJm9g9cDtAmNc3Q==

<SEC-DOCUMENT>0001246991-09-000236.txt : 20091217
<SEC-HEADER>0001246991-09-000236.hdr.sgml : 20091217
<ACCEPTANCE-DATETIME>20091217162051
ACCESSION NUMBER:		0001246991-09-000236
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20091217
FILED AS OF DATE:		20091217
DATE AS OF CHANGE:		20091217

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BURT  FRANK D
		CENTRAL INDEX KEY:			0001217093

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13087
		FILM NUMBER:		091247490

	MAIL ADDRESS:	
		STREET 1:		BOSTON PROPERTIES, INC.
		STREET 2:		800 BOYLSTON STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02199

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BOSTON PROPERTIES INC
		CENTRAL INDEX KEY:			0001037540
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
		IRS NUMBER:				042473675
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		800 BOYLSTON STREET
		STREET 2:		SUITE 1900
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02199
		BUSINESS PHONE:		6172363300

	MAIL ADDRESS:	
		STREET 1:		800 BOYLSTON STREET
		STREET 2:		SUITE 1900
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02199
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-12-17</periodOfReport>

    <issuer>
        <issuerCik>0001037540</issuerCik>
        <issuerName>BOSTON PROPERTIES INC</issuerName>
        <issuerTradingSymbol>BXP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001217093</rptOwnerCik>
            <rptOwnerName>BURT  FRANK D</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O BOSTON PROPERTIES, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>800 BOYLSTON STREET</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02199</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>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $.01</value>
            </securityTitle>
            <transactionDate>
                <value>2009-12-17</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3572</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>LTIP Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2009-12-17</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>.25</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1500</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10680</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">1,500 of the Reporting Person's units of limited partnership interest in Boston Properties Limited Partnership (BPLP), of which the Issuer is the sole general partner, were converted into common units of limited partnership interest (Common OP Units) in BPLP by the Reporting Person and the Common OP Units were redeemed for an equal number of shares of Common Stock of the Issuer in accordance with BPLP's Partnership Agreement.</footnote>
        <footnote id="F2">Represents units of limited partnership interest in BPLP issued as long term incentive compensation pursuant to the Issuer's equity based compensatory programs.  Conditioned upon minimum allocations to the capital accounts of the LTIP Units for federal income tax purposes, each LTIP Unit may be converted, at the election of the holder, into a Common OP Unit.  Each Common OP Unit may be redeemed, at the election of the holder, for cash equal to the fair market value of a share of the Issuer's Common Stock except that the Issuer may, at its election as directed by BPLP, acquire each Common OP Unit so presented for redemption for one share of Common Stock.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Kelli A. DiLuglio, as attorney-in-fact</signatureName>
        <signatureDate>2009-12-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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