EXHIBIT 5.1

                        [Shearman & Sterling Letterhead]





                                                               December 29, 1995



Alexander's, Inc.
c/o Vornado Realty Trust, Manager
Park 80 West, Plaza II
Saddle Brook, New Jersey  07663

Dear Sirs:

          We are acting as counsel for Alexander's, Inc. (the "Company") in
connection with the Registration Statement on Form S-3, as amended (Registration
Statement No. 33-62779) (the "Registration Statement"), being filed with the
Securities and Exchange Commission (the "Commission") under the Securities Act
of 1933, as amended, (the "Securities Act") relating to the offering from time
to time, as set forth in the prospectus contained in the Registration Statement
(the "Prospectus") and as to be set forth in one or more supplements to the
Prospectus (each such supplement, a "Prospectus Supplement"), of the Company's
(i) debt securities (the "Debt Securities"), (ii) warrants to purchase Debt
Securities (the "Debt Warrants"), (iii) shares of preferred stock, $1.00 par
value per share (the "Preferred Shares"), (iv) Preferred Shares represented by
depositary shares (the "Depositary Shares") and (v) shares of common stock,
$1.00 par value per share (the "Common Shares"), with an aggregate issue price
of up to $250,000,000. The Warrants, the Debt Securities, the Preferred Shares,
the Depositary Shares and the Common Shares are collectively referred to as the
"Securities". Any series of Debt Securities (as defined below) or Preferred
Shares may be convertible into Common Shares.


          The Debt Securities are to be issued from time to time in one or more
series as (i) senior debt securities (the "Senior Debt Securities") of the
Company under an indenture between the Company and State Street Bank & Trust
Company, N.A., as trustee (the "Senior Trustee"), in substantially the form
included in the Registration Statement as Exhibit 4.2 (the "Senior Indenture")
or (ii) subordinated debt securities (the "Subordinated Debt Securities") of the
Company under an indenture between the Company and State Street Bank & Trust
Company, N.A., as trustee (the "Subordinated Trustee"), in substantially the
form included in the Registration Statement as Exhibit 4.4 (the "Subordinated
Indenture"). The Debt Warrants will be issued under one or more debt warrant
agreements (each, a "Warrant Agreement") between the Company and a financial
institution identified therein as warrant




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agent (each, a "Warrant Agent"). The Depositary Shares will be issued under one
or more deposit agreements (each, a "Deposit Agreement"), each to be between the
Company and a financial institution identified therein as the depositary (the
"Depositary"), in substantially the form included in the Registration Statement
as Exhibit 4.6.

          We are familiar with the corporate proceedings of the Company to date
with respect to the proposed issuance and sale of the Securities, including
resolutions of the Board of Directors of the Company (the "Resolutions")
authorizing the Senior Indenture and the Subordinated Indenture and the
issuance, offering and sale of the Securities and we have examined such
corporate records of the Company and such other documents and certificates as we
have deemed necessary as a basis for the opinions hereinafter expressed.

          In connection with the foregoing, we have examined originals, or
copies certified or otherwise identified to our satisfaction, of such documents
and corporate and public records as we have deemed necessary as a basis for the
opinion hereinafter expressed. In our examination, we have assumed the
genuineness of all signatures, the authenticity of all documents presented to us
as originals, the conformity to the originals of all documents presented to us
as copies, and the authenticity of the originals of such documents. In rendering
our opinion, we have relied as to factual matters upon certificates of public
officials and certificates and representations of officers of the Company.

          Based on the foregoing, and having regard for such legal
considerations as we have deemed relevant, we are of the opinion that:

          1. The Senior Indenture has been duly authorized and, when executed
and delivered by the Company pursuant to the authority granted in the
Resolutions, and assuming due authorization, execution and delivery thereof by
the Senior Trustee, will constitute a valid and legally binding instrument of
the Company enforceable against the Company in accordance with its terms.

          2. The Senior Debt Securities have been duly authorized and, when the
final terms thereof have been duly established and approved and when duly
executed by the Company, in each case pursuant to the authority granted in the
Resolutions, and authenticated by the Senior Trustee in accordance with the
Senior Indenture and delivered to and paid for by the purchasers thereof, will
constitute valid and legally binding obligations of the Company entitled to the
benefits of the Senior Indenture.

          3. The Subordinated Indenture has been duly authorized and, when
executed and delivered by the Company pursuant to the authority granted in the
Resolutions, and assuming due authorization, execution and delivery thereof by
the Subordinated Trustee, will constitute a valid and legally binding instrument
of the Company enforceable against the Company in accordance with its terms.




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          4. The Subordinated Debt Securities have been duly authorized and,
when the final terms thereof have been duly established and approved and when
duly executed by the Company, in each case pursuant to the authority granted in
the Resolutions, and authenticated by the Subordinated Trustee in accordance
with the Subordinated Indenture and delivered to and paid for by the purchasers
thereof, will constitute valid and legally binding obligations of the Company
entitled to the benefits of the Subordinated Indenture.

          5. The Warrant Agreements have been duly authorized and, when the
final terms thereof have been duly established and approved and when duly
executed and delivered by the Company, in each case pursuant to the authority
granted in the Resolutions, and, assuming due authorization, execution and
delivery thereof by the applicable Warrant Agent, will constitute valid and
legally binding instruments of the Company enforceable against the Company in
accordance with their respective terms.

          6. The Debt Warrants have been duly authorized and, when the final
terms thereof have been duly established and approved and when duly executed by
the Company, in each case pursuant to the authority granted in the Resolutions,
and countersigned by the applicable Warrant Agent in accordance with the
applicable Warrant Agreement and delivered to and paid for by the purchasers
thereof, will constitute valid and legally binding obligations of the Company
enforceable against the Company in accordance with their respective terms.

          7. The Preferred Shares have been duly authorized and, when the final
terms thereof have been duly established and approved and certificates
representing such shares have been duly executed by the Company, in each case
pursuant to the authority granted in the Resolutions, and delivered to and paid
for by the purchasers thereof, and when all corporate action necessary for
issuance of such shares has been taken, including the adoption of a Certificate
of Designation, such shares will be validly issued, fully paid and
nonassessable.

          8. The Deposit Agreements have been duly authorized and, when the
final terms thereof have been duly established and approved and when duly
executed and delivered by the Company, in each case pursuant to the authority
granted in the Resolutions, and assuming due authorization, execution and
delivery thereof by the applicable Depositary, will constitute valid and legally
binding instruments of the Company enforceable against the Company in accordance
with their respective terms.

          9. The Depositary Shares have been duly authorized and, when the final
terms thereof have been duly established and approved, in each case pursuant to
the authority granted in the Resolutions, and when the depositary receipts
representing the Depositary Shares (the "Depositary Receipts") have been duly
executed by the Depositary and delivered to and paid for by the purchasers
thereof, and when all corporate action necessary for




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issuance of Depositary Shares and the underlying Preferred Shares has been
taken, such Depositary Shares will be validly issued and will entitle the
holders thereof to the rights specified in the Depositary Receipts and the
Deposit Agreement.

          10. The Common Shares have been duly authorized and, when issued and
delivered pursuant to the authority granted in the Resolutions and against
payment therefor, will be validly issued, fully paid and non-assessable.

          11. The Common Shares issuable upon conversion of any issue of
convertible Debt Securities or Preferred Shares have been duly authorized and,
when issued and delivered upon conversion of such Debt Securities or Preferred
Shares, will be validly issued, fully paid and non-assessable.

          The opinions set forth above are subject, as to enforcement, to (i)
bankruptcy, insolvency (including, without limitation, all laws relating to
fraudulent transfers), reorganization, moratorium or other similar laws relating
to or affecting the enforcement of creditors' rights generally, (ii) general
equitable principles (regardless of whether enforcement is considered in a
proceeding in equity or at law) and (iii) provisions of law that require that a
judgment for money damages rendered by a court in the United States be expressed
only in United States dollars.

          We hereby consent to the use of this opinion as an exhibit to the
Registration Statement and to the use of our name under the heading "Validity of
the Securities" in the Prospectus. In giving such consent, we do not thereby
admit that we are within the category of persons whose consent is required under
Section 7 of the Securities Act.


                                                    Very truly yours,

                                                    /s/  SHEARMAN & STERLING