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                                                                     EXHIBIT 5.1



                                  June __, 1998



AMB Property, L.P.
AMB Property Corporation
505 Montgomery Street
San Francisco, California  94111

        Re:     Registration Statement on Form S-11 in connection with the
                issuance of $350,000,000 Aggregate Principal Amount of Debt
                Securities of AMB Property, L.P. (File No. 333-49163)

Ladies and Gentlemen:

        We have acted as special counsel to AMB Property, L.P., a Delaware
limited partnership (the "Operating Partnership"), and AMB Property Corporation,
a Maryland corporation (the "Corporation" and together with the Operating
Partnership, the "Registrants") in connection with the registration by the
registrants under the Securities Act of 1933, as amended, of $350,000,000
aggregate principal amount of debt securities of the Operating Partnership (the
"Securities"), guaranteed by the Corporation (the "Guarantees") on a Form S-11
Registration Statement, dated April 2, 1998 (File No. 333-49163), as amended
(the "Registration Statement"), as filed with the Securities and Exchange
Commission (the "Commission"). We also have examined the draft indenture between
AMB Property, L.P. (the "Operating Partnership"), AMB Property Corporation, a
Maryland corporation, and State Street Bank and Trust Company of California,
N.A., as trustee (the "Trustee"), as supplemented by the First Supplemental
Indenture, Second Supplemental Indenture and Third Supplemental Indenture
thereto (collectively, the "Indenture"), drafts of which have been filed as
exhibits to the Registration Statement.

        In our capacity as your special counsel in connection with such
registration, we are familiar with the proceedings taken and proposed to be
taken by the Operating Partnership and the Corporation in connection with the
authorization and issuance of the Securities and, for 


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AMB Property, L.P.
AMB Property Corporation
June ___, 1998
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the purposes of this opinion, have assumed such proceedings will be timely
completed in the manner presently proposed and that the terms of each issuance
will otherwise be in compliance with law. In addition, we have assumed that the
Operating Partnership is a partnership duly organized, validly existing and in
good standing under the laws of the State of Delaware, with full power and
authority to execute, deliver and perform its obligations under the Securities
and the Indenture, and that the Corporation is a corporation duly incorporated,
validly existing and in good standing under the laws of the State of Maryland,
with full power and authority to execute, deliver and perform its obligations
under the Guarantees and the Indenture. In addition, we have made such legal and
factual examinations and inquiries, including an examination of originals or
copies certified or otherwise identified to our satisfaction of such documents,
corporate records and instruments, as we have deemed necessary or appropriate
for purposes of this opinion.

        We are opining herein as to the effect on the subject transaction only
of the internal laws of the State of New York and we express no opinion with
respect to the applicability thereto, or the effect thereon, of the laws of any
other jurisdiction or as to any matters of municipal law or the laws of any
other local agencies within any state. In rendering the opinion set forth below
as it relates to the laws of the State of Maryland, we have with your consent
relied solely upon the opinion of Ballard Spahr Andrews & Ingersoll, special
Maryland counsel to the Corporation, addressed to us and dated the date hereof,
and our opinion is subject to any assumptions, exceptions, qualifications or
limitations set forth in such opinion.

        In our examination, we have assumed the genuineness of all signatures,
the authenticity of all documents submitted to us as originals, and the
conformity to authentic original documents of all documents submitted to us as
copies.

        Subject to the foregoing and the other matters set forth herein, it is
our opinion that, as of the date hereof:

        1. Upon establishment by the Corporation, in its capacity as general
partner of the Operating Partnership (the "General Partner"), of the terms,
conditions and provisions of the Securities and due authorization by the General
Partner of the Securities for issuance at a minimum price or value of
consideration to be set by the General Partner, the Securities will have been
duly authorized by the Operating Partnership, and, assuming the authorization,
execution and delivery of the Indenture by all of the parties thereto in the
form filed as an exhibit to the Registration Statement, and when duly
authenticated by the Trustee and duly executed and delivered on behalf of the
Operating Partnership against payment therefor in accordance with the terms and
provisions of the Indenture and as contemplated by the Registration Statement,
the Securities will constitute valid and binding obligations of the Operating
Partnership, enforceable against the Operating Partnership in accordance with
their terms.

        2. Upon the authorization, execution and delivery of the Indenture by
all of the parties thereto in the form filed as an exhibit to the Registration
Statement, and when the 


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AMB Property, L.P.
AMB Property Corporation
June ___, 1998
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Securities have been duly authenticated by the Trustee and duly executed and
delivered on behalf of the Operating Partnership against payment therefor in
accordance with the terms and provisions of the Indenture and as contemplated by
the Registration Statement, the Guarantees will constitute valid and binding
obligations of the Corporation, enforceable against the Corporation in
accordance with their terms.

        The opinions rendered above are subject to the following exceptions,
limitations and qualifications: (i) the effect of bankruptcy, insolvency,
reorganization, moratorium or other similar laws now or hereafter in effect
relating to or affecting the rights and remedies of creditors; (ii) the effect
of general principles of equity, whether enforcement is considered in a
proceeding in equity or law, and the discretion of the court before which any
proceeding therefor may be brought; (iii) we express no opinion concerning the
enforceability of the waiver of rights or defenses contained in Section 5.14 of
the Indenture; and (iv) we express no opinion with respect to whether
acceleration of the Securities may affect the collectibility of that portion of
the stated principal amount thereof which might be determined to constitute
unearned interest thereon.

        To the extent that the obligations of the Operating Partnership and the
Corporation under the Indenture may be dependent upon such matters, we assume
for purposes of this opinion that the Trustee is duly organized, validly
existing and in good standing under the laws of its jurisdiction of
organization; that the Trustee is duly qualified to engage in the activities
contemplated by the Indenture; that the Indenture has been duly authorized,
executed and delivered by the Trustee and constitutes the legally valid, binding
and enforceable obligation of the Trustee enforceable against the Trustee in
accordance with its terms; that the Trustee is in compliance, generally and with
respect to acting as a trustee under the Indenture, with all applicable laws and
regulations; and that the Trustee has the requisite organizational and legal
power and authority to perform its obligations under the Indenture.

        We consent to your filing this opinion as an exhibit to the Registration
Statement and to the reference to our firm under the caption "Legal Matters" in
the prospectus included therein.

                                             Very truly yours,



                                             /s/ LATHAM & WATKINS
