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                                                                     EXHIBIT 8.1

                         [LATHAM & WATKINS LETTERHEAD]


                                  May ___, 1998


AMB Property Corporation
505 Montgomery Street
San Francisco, California 94111

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

        Re:     Registration Statement on Form S-11 of AMB Property Corporation,
                AMB Property, L.P., AMB Property II, L.P., and Long Gate LLC;
                Federal Income Tax Considerations

Ladies and Gentlemen:

               We have acted as tax counsel to AMB Property, L.P., a Delaware
limited partnership (the "Operating Partnership") of which AMB Property
Corporation, a Maryland corporation (the "Company"), is the sole general
partner, and the Company in connection with the sale by the Operating
Partnership of up to 350,000,000 aggregate principal amount of ___% Notes due
2008, ___% Notes due 2018, and ___ Reset Put Securities (REPSSM) due 2015,
pursuant to a registration statement on Form S-11, filed with the Securities and
Exchange Commission on April 2, 1998 (file number 333-_________) by the Company,
the Operating Partnership, and Long Gate LLC, a Delaware limited liability
company in which AMB Property Holding Corporation, a Delaware corporation and
wholly-owned subsidiary of the Company, is the sole managing member and in which
the Operating Partnership is the sole non-managing member (as amended as of the
date hereof and including each document incorporated by reference therein, the
"Registration Statement").


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AMB Property Corporation 
AMB Property, L.P.
May ___, 1998
Page 2


               You have requested our opinion concerning certain of the Federal
income tax consequences to the purchasers of the securities described above in
connection with the sale described above. This opinion is based on various facts
and assumptions, including the facts set forth in the Registration Statement
concerning the business, properties and governing documents of the Company, the
Operating Partnership, and their subsidiaries.

               In our capacity as tax counsel to the Operating Partnership, 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 other instruments as we
have deemed necessary or appropriate for purposes of this opinion. In our
examination, we have assumed the authenticity of all documents submitted to us
as originals, the genuineness of all signatures thereon, the legal capacity of
natural persons executing such documents and the conformity to authentic
original documents of all documents submitted to us as copies.

               We are opining herein as to the effect on the subject transaction
only of the Federal income tax laws of the United States and we express no
opinion with respect to the applicability thereto, or the effect thereon, of
other Federal laws, the laws of any state or other jurisdiction or as to any
matters of municipal law or the laws of any other local agencies within any
state.

               Based on such facts, assumptions and representations, it is our
opinion that the information in the Registration Statement set forth under the
caption "Certain Federal Income Tax Considerations Relating To The REPS," to the
extent that it constitutes matters of law, summaries of legal matters or legal
conclusions, has been reviewed by us and is accurate in all material respects.

               No opinion is expressed as to any matter not discussed herein.

               This opinion is only being rendered to you as of the date of this
letter, and we undertake no obligation to update this opinion if there are
changes in the law subsequent to the date hereof. This opinion is based on
various statutory provisions, regulations promulgated thereunder and
interpretations thereof by the Internal Revenue Service and the courts having
jurisdiction over such matters, all of which are subject to change either
prospectively or retroactively. Also, any variation or difference in the facts
from those set forth in the Registration Statement may affect the conclusions
stated herein.

               This opinion is rendered only to you, and is solely for your use
and the use of your shareholders or partners (as the case may be) in connection
with the transactions set forth in the Registration Statement. This opinion may
not be relied upon by you or your shareholders or partners (as the case may be)
for any other purpose, or furnished to, quoted to, 


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AMB Property Corporation 
AMB Property, L.P.
May ___, 1998
Page 3

or relied upon by any other person, firm or corporation, for any purpose,
without our prior written consent. We hereby consent to the filing of this
opinion as an exhibit to the Registration Statement and to the use of our name
under the caption "Legal Matters" in the Registration Statement.

                                        Very truly yours,

