EXHIBIT 5.1

                    [LETTERHEAD OF THACHER PROFFITT & WOOD]



Writer's Direct Dial
(212) 912-7815



                                    February 18, 2000


Astoria Capital Trust I
Astoria Financial Corporation
One Astoria Federal Plaza
Lake Success, New York 11042

                    Re:  Astoria Capital Trust I
                         Registration Statement on Form S-4
                         ----------------------------------

Ladies and Gentlemen:

     We have acted as special counsel to Astoria Financial Corporation, a
Delaware corporation (the "Corporation") and Astoria Capital Trust I, a Delaware
statutory business trust (the "Trust"), in connection with the preparation and
filing by the Corporation and the Trust with the Securities and Exchange
Commission (the "Commission") of an exchange offer registration statement (the
"Registration Statement") on Form S-4 under the Securities Act of 1933, as
amended (the "Act"), relating to (i) the issuance of up to 125,000 9.75% Capital
Securities, Series B (liquidation amount of $1,000 per capital security) of the
Trust (the "Exchange Capital Securities"), representing preferred beneficial
interests in the assets of the Trust under the Amended and Restated Declaration
of Trust, dated as of October 28, 1999 (the "Declaration"), by and among the
Corporation, Wilmington Trust Company, as Property Trustee (the "Property
Trustee"), Wilmington Trust Company, as Delaware Trustee (the "Delaware
Trustee"), and the Administrative Trustees named therein, (ii) the issuance of
up to $128,866,000 principal amount of 9.75% Junior Subordinated Deferrable
Interest Debentures due November 1, 2029, Series B (the "Exchange Debentures"),
by the Corporation pursuant to the Indenture, dated as of October 28, 1999 (the
"Indenture"), between the Corporation and Wilmington Trust Company, as Debenture
Trustee and (iii) the Series B Capital Securities Guarantee Agreement, dated as
of February 18, 2000 (the "Exchange Guarantee"), between the Corporation and
Wilmington Trust Company, as Guarantee Trustee (the "Guarantee Trustee"),
relating to the Exchange Capital Securities.


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Astoria Financial Corporation
Astoria Capital Trust I
February 18, 2000

     This opinion is being furnished in accordance with the requirements of Item
601(b)(5) of Regulation S-K under the Act.  Capitalized terms used and not
defined herein shall have the respective meanings set forth in the Registration
Statement.

     In connection with this opinion, we have examined originals or copies,
certified or otherwise identified to our satisfaction, of the following:

     (i)    Copy of the Certificate of Incorporation of the Corporation,
     certified as of a recent date by the Secretary of State of the State of
     Delaware;

     (ii)   Copy of the Bylaws of the Corporation, certified by the Secretary of
     the Corporation to be a true, correct and complete copy;

     (iii)  Certificate as of a recent date of the Secretary of State of the
     State of Delaware certifying as to the good standing of the Corporation
     under the laws of the State of Delaware;

     (iv)   Executed copy of the Certificate of Trust of the Trust filed with
the Secretary of State of the State of Delaware on October 19, 1999;

     (v)    Certificate as of a recent date of the Secretary of State of the
State of Delaware certifying as to the good standing of the Trust under the laws
of the State of Delaware;

     (vi)   Copies, certified by the Secretary of the Corporation to be true,
correct and complete copies, of the resolutions duly adopted by the Board of
Directors of the Corporation on October 20, 1999;

     (vii)  Executed copy of the Written Consent of the Administrative
Trustees dated February 16, 2000;

     (viii) Copy of the Registration Statement on Form S-4 filed by the
Corporation and the Trust with the Commission on February 18, 2000 under the
Act;

     (ix)   Executed copy of the Declaration of Trust, dated as of October 18,
1999, by and between the Corporation and the Delaware Trustee;

     (x)    Executed copy of the Declaration;

     (xi)   Form of certificates evidencing the Exchange Capital Securities;

     (xii)  Executed copy of the Exchange Guarantee;

     (xiii) Executed copy of the Indenture;

     (xiv)  Form of certificate evidencing the Exchange Debentures; and

     (xv)   Executed copy of the Registration Rights Agreement, dated as of
October 25, 1999


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Astoria Financial Corporation
Astoria Capital Trust I
February 18, 2000

(the "Registration Rights Agreement"), by and among the Corporation, the Trust
and the Initial Purchaser.

     We have also examined originals or copies, certified or otherwise
identified to our satisfaction, of such other documents, certificates and
records, and we have examined such matters of law, as we have deemed necessary
or appropriate as a basis for the opinions set forth herein.

     In our examination, we have assumed the legal capacity of all natural
persons, the genuineness of all signatures, the authenticity of all documents
submitted to us as originals, the conformity to original documents of all
documents submitted to us as certified or photostatic copies and the
authenticity of the originals of such latter documents. In making our
examination of documents executed by parties other than the Corporation and the
Administrative Trustees, we have assumed that such parties had the power,
corporate or other, to enter into and perform all obligations thereunder and
have also assumed the due authorization by all requisite action, corporate or
other, and execution and delivery by such parties of such documents, and the
validity and binding effect and enforceability thereof on such parties.  As to
any facts material to the opinions expressed herein which we did not
independently establish or verify, we have relied upon oral or written
statements and representations of the trustees of the Trust, representatives of
the Corporation and others and the accuracy of the facts, information, covenants
and representations set forth in the documents listed above.  We have assumed
the accuracy of all statements of fact, and we did not independently establish
or verify the facts, information, covenants and representations set forth in the
documents listed above.  We have not, except as specifically identified herein,
been retained or engaged to perform and, accordingly have not performed, any
independent review or investigation of any statutes, ordinances, laws,
regulations, agreements, contracts, instruments, corporate records, orders,
writs, judgments, rules or decrees to which the Corporation or the Trust may be
a party or to which the Corporation or the Trust or any property thereof may be
subject or bound.  The opinions expressed below, and all statements herein "to
the best of our knowledge" or "to our attention" are made in the context of the
foregoing.  "To the best of our knowledge" or "to our attention" as used herein
means the actual knowledge of our attorneys who have worked on this transaction.

     Based upon and subject to the limitations, qualifications, exceptions and
assumptions set forth herein, we are of the opinion that:

     1.   The Exchange Capital Securities have been duly authorized for issuance
by the Trust and, when the Declaration has been qualified under the Trust
Indenture Act of 1939, as amended, and when the Exchange Capital Securities are
duly issued, executed and authenticated in the manner provided for in the
Declaration and delivered and issued in the exchange offer as contemplated by
the Registration Rights Agreement and the Registration Statement, the Exchange
Capital Securities will be validly issued and, subject to the qualifications set
forth in paragraph 4 below, fully paid and nonassessable undivided beneficial
interests in the assets of the Trust and will entitle the holders thereof to the
benefits of the Declaration.

     2.   The Exchange Debentures have been duly authorized for issuance by the
Corporation pursuant to the Indenture and, when the Indenture has been qualified
under the Trust Indenture Act of 1939, as amended, and when the Exchange
Debentures are executed, authenticated and delivered in the manner provided for
in the exchange offer as contemplated in the Registration Rights Agreement, the
Exchange Debentures will constitute valid and binding obligations of the
Corporation and will entitle the


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Astoria Financial Corporation
Astoria Capital Trust I
February 18, 2000

holders thereof to the benefits of the Indenture, enforceable against the
Corporation in accordance with their terms, except as rights to indemnity and
contribution thereunder may be limited under applicable law or public policy,
and subject to the qualifications that (i) enforcement thereof may be limited by
bankruptcy, insolvency, receivership, reorganization, liquidation, voidable
preference, moratorium or other laws (including the laws of fraudulent
conveyance and transfer) or judicial decisions affecting the enforcement of
creditors' rights generally or the reorganization of financial institutions and
(ii) the enforceability of the Corporation's obligations thereunder is subject
to general principles of equity (regardless of whether such enforceability is
considered in a proceeding in equity or at law) and to the effect of certain
laws and judicial decisions upon the availability and enforceability of certain
remedies, including the remedies of specific performance and self-help.

     3.   The Exchange Guarantee has been duly authorized by the Corporation
and, when the Exchange Guarantee has been qualified under the Trust Indenture
Act of 1939, as amended, and when the Exchange Guarantee is executed,
authenticated and delivered in the manner provided for in the exchange offer as
contemplated in the Registration Rights Agreement, the Exchange Guarantee will
constitute a valid and binding instrument of the Corporation, enforceable
against the Corporation in accordance with its terms, except as rights to
indemnity and contribution thereunder may be limited under applicable law or
public policy, and subject to the qualifications that (i) enforcement thereof
may be limited by bankruptcy, insolvency, receivership, reorganization,
liquidation, voidable preference, moratorium or other laws (including the laws
of fraudulent conveyance and transfer) or judicial decisions affecting the
enforcement of creditors' rights generally or the reorganization of financial
institutions and (ii) the enforceability of the Corporation's obligations
thereunder is subject to general principles of equity (regardless of whether
such enforceability is considered in a  proceeding in equity or at law) and to
the effect of certain laws and judicial decisions upon the availability and
enforceability of certain remedies, including the remedies of specific
performance and self-help.

     4.   The holders of the Exchange Capital Securities are entitled to the
same limitation of personal liability extended to stockholders of private
corporations for profit organized under the General Corporation Law of the State
of Delaware; it being understood, however, that the holders of the Exchange
Capital Securities may be obligated, pursuant to the Declaration, to provide (i)
indemnity and/or security in connection with and pay taxes or governmental
charges arising from transfers or exchanges of certificates evidencing such
capital securities ("Capital Security Certificates") and the issuance of
replacement Capital Security Certificates, and (ii) security or indemnity in
connection with requests of or directions to the Property Trustee to exercise
its rights and powers under the Declaration.

     In rendering the opinions set forth above, we have not passed upon and do
not purport to pass upon the application of securities or "blue-sky" laws of any
jurisdiction (except federal securities laws).

     We are members of the Bar of the State of New York, and we express no
opinion as to the laws of any jurisdiction other than the law of the State of
New York, the corporate law of the State of Delaware, the law of the State of
Delaware concerning the treatment of Delaware business trusts and the federal
law of the United States of America, and we do not express any opinion
concerning the application of the "doing business" laws or the securities laws
of any jurisdiction other than the federal securities laws of the United States
of America.  We do not express any opinion on any issue not expressly addressed
above.


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Astoria Financial Corporation
Astoria Capital Trust I
February 18, 2000


     We assume no obligation to advise you of any changes in the foregoing
subsequent to the delivery of this opinion.  This opinion letter is rendered for
the benefit of the Corporation, the Trust and the holders of the Exchange
Capital Securities.  Copies of this opinion letter may not be furnished to any
other person, nor may any portion of this opinion letter be quoted, circulated
or referred to in any other document, without our prior written consent.

     We consent to the filing of this opinion as an Exhibit to the Registration
Statement, and to the reference to our firm under the heading "Legal Matters" in
the prospectus which is part of the Registration Statement.


                                                Very truly yours,

                                                Thacher Proffitt & Wood

                                                By: /s/ Robert C. Azarow
                                                   ---------------------
                                                    Robert C. Azarow