EXHIBIT 8.1




                        [MCCARTER & ENGLISH, LETTERHEAD]







                                          September 12, 2003

One Liberty Properties, Inc.
60 Cutter Mill Road
Great Neck, NY 11021

Ladies and Gentlemen:

      This opinion is furnished in connection with the registration on Form S-3
(the "Registration Statement") pursuant to the Securities Act of 1933, as
amended, of the public offering and sale, from time to time in one or more
offerings up to an aggregate public offering price of $200,000,000, of common
stock (the "Shares"), par value $1.00 per share, of One Liberty Properties, Inc.
(the "Company"). This opinion relates solely to the Company's qualification for
federal income tax purposes as a real estate investment trust within the meaning
of Sections 856 through 860 of the Internal Revenue Code of 1986, as amended
(the "Code").

      For purposes of delivering this opinion, we have examined the Articles of
Incorporation (including related Articles of Amendment) and Bylaws of the
Company, the Registration Statement and such other records, certificates and
documents as we have deemed necessary or appropriate for purposes of rendering
the opinion set forth herein. We have relied upon the representations of a duly
appointed officer of the Company contained in a letter dated as of this date
(the "Officer's Certificate") regarding various factual matters, including the
manner in which the Company has been and will continue to be operated. We have
assumed that each representation in the Officer's Certificate is and will be
true, correct and complete and that all representations that (a) address future
matters or conditions, (b) address the intentions of, or (c) are given to the
best of the belief and/or knowledge of any person(s) or party(ies) are and will
be true, correct and complete as if made without such qualification. We assume
that the Company will be operated in accordance with all applicable laws and the
terms and conditions of applicable documents. In addition, we have relied upon
certain additional facts and assumptions described below.

      In rendering the opinion set forth herein, we have assumed (i) the
genuineness of all signatures on documents we have examined, (ii) the
authenticity of all documents submitted to us as originals, (iii) the conformity
to the original documents of all documents submitted to us as copies, (iv) the
conformity of final documents to all documents submitted to us as drafts, (v)
the authority and capacity of the individual or individuals who executed any
such documents on behalf of any person, (vi) the accuracy and completeness of
all records made available to us, and (vii) the factual accuracy of all
representations, warranties and other statements made in the

One Liberty Properties, Inc.
September 12, 2003
Page 2

Registration Statement. In addition, we have assumed that for the remainder of
2003 and in subsequent taxable years, the Company will operate in a manner that
will make the representations contained in the Officer's Certificate true for
all such years, and that the Company will not make any amendments to its
organizational documents (or to those of its incorporated and/or unincorporated
subsidiaries) after the date of this opinion that would affect the Company's
qualification as a real estate investment trust for any taxable year. For
purposes of this opinion, we have made no independent investigation of the
factual matters contained in the documents set forth above, or in the
representations set forth in the Officer's Certificate and/or the Registration
Statement. No facts have come to our attention, however, that would cause us to
question the accuracy and completeness of such facts or factual representations
in a material way.

      The opinion set forth below is based upon the Code, the Income Tax
Regulations and Procedure and Administration Regulations promulgated thereunder
and administrative and judicial interpretations thereof, in each case as they
currently exist and all of which are subject to change, and the opinion below is
rendered as of the date hereof, and we disclaim any obligation to advise you of
any change in any of the foregoing sources of law or subsequent developments in
law or changes in facts or circumstances which might affect any matters or
opinion set forth herein. No assurance can be given that the federal income tax
consequences described below will not be altered in the future.

      Based on the documents and assumptions set forth above and the
representations set forth in the Officer's Certificate, and provided that the
Company continues to meet the applicable asset composition, source of income,
shareholder diversification, distribution, and other requirements of the Code
necessary for a corporation to qualify as a real estate investment trust, we are
of the opinion that:

      (1) Commencing with the Company's taxable year ended December 31, 2002,
the Company has been organized and operated in conformity with the requirements
for qualification as a "real estate investment trust" under the Code, and its
method of operation enables it to continue to meet the requirements for
qualification as a "real estate investment trust" under the Code, provided that
the Company continues to meet the applicable asset composition, source of
income, shareholder diversification, distribution, record-keeping and other
requirements of the Code necessary for a corporation to qualify as a real estate
investment trust, and

      (2) The information in the Registration Statement under the caption
"Certain Federal Income Tax Considerations," to the extent that it constitutes
matters of law or legal conclusions, has been reviewed by us and is correct in
all material respects, and our opinion set forth in such discussion is
confirmed.

      We will not review, on a continuing basis, the Company's compliance with
the documents or assumptions set forth above, or the representations set forth
in the Officer's

One Liberty Properties, Inc.
September 12, 2003
Page 3

Certificate. Accordingly, no assurance can be given that the actual results of
the Company's operations for any given taxable year will satisfy the
requirements for qualification and taxation as a real estate investment trust
under the Code. The ability of the Company to continue to meet the requirements
for qualification and taxation as a real estate investment trust will be
dependent upon the Company's ability to continue to meet in each year the
applicable asset composition, source of income, shareholder diversification,
distribution, and other requirements of the Code necessary for a corporation to
qualify as a real estate investment trust.

      The foregoing opinion is limited to the federal income tax matters
addressed herein, and no other opinion is rendered with respect to other federal
tax matters or to any issues arising out of the tax laws of any state or
locality. We express no opinion with respect to the matters described herein
other than those expressly set forth herein. You should recognize that our
opinion is not binding on the Internal Revenue Service and that the Internal
Revenue Service may disagree with the opinion contained herein. Although we
believe that our opinion will be sustained if challenged, there is no guarantee
that this will be the case. Except as specifically discussed above, the opinion
expressed herein is based upon the laws that currently exist. Consequently,
future changes in the law may cause the federal income tax treatment of the
Company to be materially and adversely different from that described above.

      We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to our firm under the caption
"Certain Federal Income Tax Considerations" in the Registration Statement. In
giving such consent, we do not thereby admit that we are in the category of
persons whose consent is required under Section 7 of the Securities Act of 1933,
as amended, or the rules and regulations of the Securities and Exchange
Commission thereunder.


                                          Very truly yours,

                                          /s/ McCarter & English, LLP

                                          McCarter & English, LLP