EXHIBIT 5.1

                                                              September __, 1997

Banknorth Capital Trust I
c/o Banknorth Group, Inc.
    300 Financial Plaza
    Burlington, Vermont 05401

            Re:   Banknorth Group, Inc.
                  Banknorth Capital Trust I
                  Registration Statement on Form S-4
                  ----------------------------------

Ladies and Gentlemen:

            We have acted as counsel to Banknorth Group, Inc., a Delaware
corporation (the "Corporation") and Sponsor of Banknorth Capital Trust I, a
Delaware statutory business trust (the "Trust"), in connection with a
Registration Statement on Form S-4 (the "Registration Statement") relating to:
(i) the proposed issuance by the Trust of up to and including $30,000,000
aggregate Liquidation Amount of its 10.52% Capital Securities, Series B (the
"Exchange Capital Securities") registered under the Securities Act of 1933, as
amended (the "Securities Act"), in exchange for up to and including $30,000,000
aggregate Liquidation Amount of its outstanding 10.52% Capital Securities,
Series A (the "Original Capital Securities"); (ii) the proposed issuance by the
Corporation to the Trust, in an aggregate principal amount corresponding to the
aggregate Liquidation Amount of the Exchange Capital Securities, of the
Corporation's 10.52% Junior Subordinated Deferrable Interest Debentures
due May 1, 2027, Series B (the "Exchange Junior Subordinated Debentures")
registered under the Securities Act in exchange for a comparable aggregate
principal amount of the Corporation's outstanding 10.52% Junior Subordinated
Deferrable Interest Debentures due May 1, 2027, Series A (the "Original Junior
Subordinated Debentures"); and (iii) the proposed execution of the Corporation's
guarantee in respect of the Exchange Capital Securities (the "Exchange
Guarantee") registered under the Securities Act. The Exchange Capital Securities
will be issued under an Amended and Restated Declaration of Trust for the Trust,
dated as of May 1, 1997 (the "Amended Declaration"), among the Corporation, as
Sponsor, The First National Bank of Chicago, as Property Trustee, First Chicago
Delaware Inc., as Delaware Trustee, and the Administrative Trustees named
therein, while the Exchange Junior Subordinated Debentures will be issued
under an

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Indenture, dated as of May 1, 1997 (the "Indenture"), between the Corporation
and The First National Bank of Chicago, as Debenture Trustee.

      We have examined such documents and records as we deemed appropriate,
including 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 By-Laws of the Corporation, certified by the
      Secretary of the Corporation to be a true and complete copy;

            (iii) Copy, certified by the Secretary of the Corporation to be a
      true and complete copy, of the resolutions duly adopted by the Board of
      Directors of the Corporation on September 22, 1997, as supplemented by a
      certificate of the President, dated September 23, 1997 relating thereto;

            (iv) Executed counterparts of the Amended Declaration.

            (v) Specimen of the Exchange Capital Security.

            (vi) Executed counterparts of the Indenture.

            (vii) Specimen of the Exchange Junior Subordinated Debenture.

            (viii) Executed counterparts of the Exchange Guarantee.

            (ix) Executed counterparts of the Registration Rights Agreement,
      dated as of May 1, 1997 (the "Registration Rights Agreement"), among the
      Trust, the Corporation and the Initial Purchasers named therein.

      In addition, as to certain factual matters, we have relied upon
certificates of officers of the Corporation, public officials and others.

      In the course of 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 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, as well as the validity, binding effect and
enforceability thereof on such parties.


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      Based upon the foregoing, we are of the opinion that:

      (1) The Exchange Junior Subordinated Debentures have been duly authorized
by all requisite corporate action of the Corporation and, when executed and
authenticated in the manner provided for in the Indenture and delivered against
surrender and cancellation of a like aggregate principal amount of Original
Junior Subordinated Debentures as contemplated in the Registration Rights
Agreement, the Exchange Junior Subordinated Debentures will constitute valid and
binding obligations of the Corporation entitled to the benefits of the Indenture
and enforceable against the Corporation in accordance with their terms, except
as enforcement thereof may be limited by bankruptcy, insolvency, reorganization,
moratorium or other similar laws relating to or affecting creditors' rights
generally or by general equitable principles (regardless of whether considered
in a proceeding in equity or at law).

      (2) The Exchange Guarantee has been duly authorized by all requisite
corporate action of the Corporation and, when executed by the Corporation and
The First National Bank of Chicago, as Guarantee Trustee, and delivered as
contemplated in the Registration Rights Agreement, the Exchange Guarantee will
constitute a valid and binding agreement of the Corporation, enforceable against
the Corporation in accordance with its terms, except as enforcement thereof may
be limited by bankruptcy, insolvency, reorganization, moratorium or other
similar laws relating to or affecting creditors' rights generally or by general
equitable principles (regardless of whether considered in a proceeding in equity
or at law).

      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 laws of the State of
New York and the federal laws of the United States of America. As to matters
governed by Delaware law, we have relied exclusively upon the opinion of
Richards, Layton & Finger and have not made any independent investigation
thereof.

      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
"Validity of Exchange Securities" in the Prospectus included therein.

                                       Very truly yours,


                                       BROWN & WOOD LLP


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