Exhibit 5.1

                [Letterhead LeBoeuf, Lamb, Greene & MacRae LLP]



                                                              December 21, 2006


MetLife, Inc.
27-01 Queens Plaza North
Long Island City, New York 11101


     Re:  MetLife, Inc.
          6.40% Fixed-to-Floating Rate Junior Subordinated Debentures due 2066
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Ladies and Gentlemen:

      We have acted as special counsel to MetLife, Inc., a Delaware corporation
(the "Company"), in connection with the sale by the Company of $1,250,000,000 in
aggregate principal amount of its 6.40% Fixed-to-Floating Rate Junior
Subordinated Debentures due 2066 (the "Securities") to the Underwriters named in
Schedule I to the Pricing Agreement dated December 14, 2006 (the "Pricing
Agreement" and such firms, the "Underwriters"). The Securities will be issued
under the Subordinated Indenture, dated as of June 21, 2005 (the "Base
Indenture"), as supplemented by the Third Supplemental Indenture, dated as of
December 21, 2006 (the "Supplemental Indenture" and, together with the Base
Indenture, the "Indenture"), between the Company and The Bank of New York Trust
Company, N.A. (as successor in interest to J.P. Morgan Trust Company, National
Association), as trustee (the "Trustee").

      In connection therewith, we have examined: (a) the Registration Statement
on Form S-3 (Registration No. 333-124358) relating to the Securities and other
securities filed by the Company with the Securities and Exchange Commission (the
"Commission") under the Securities Act of 1933, as




December 21, 2006
Page 2


amended (the "Act"), which was declared effective under the Act on May 27, 2005,
allowing for delayed offerings pursuant to Rule 415 under the Act (the
"Registration Statement"); (b) the prospectus, dated April 27, 2005 (the "Base
Prospectus"), which forms a part of and is included in the Registration
Statement; (c) the prospectus supplement, dated December 14, 2006, relating to
the offering of the Securities and (together with the Base Prospectus, the
"Prospectus"), in the form filed by the Company with the Commission on December
18, 2006 pursuant to Rule 424(b) under the Act; (d) an executed copy of the
Underwriting Agreement, dated December 14, 2006, between the Company and the
representatives of the Underwriters (the "Underwriting Agreement"); (e) an
executed copy of the Pricing Agreement; (f) copies of the certificates, dated
December 21, 2006 representing in the aggregate $1,250,000,000 principal amount
of the Securities; (g) an executed copy of the Base Indenture; (h) an executed
copy of the Supplemental Indenture; and (i) such records of the corporate
proceedings of the Company as we have deemed necessary as the basis for the
opinions expressed herein.

      In addition, we have examined the originals (or copies certified or
otherwise identified to our satisfaction) of such other agreements, instruments,
certificates, documents and records and have reviewed such questions of law and
made such inquiries as we have deemed necessary or appropriate for the purposes
of the opinion rendered herein.

      In such examination, we have assumed, without inquiry, the legal capacity
of all natural persons, the genuineness of all signatures on all documents
examined by us, the authenticity of all documents submitted to us as originals,
the conformity to original documents of all documents submitted to us as
facsimile, electronic, certified/or photostatic copies and the authenticity of
such originals. We have also assumed that the books and records of the Company
are maintained in accordance with proper corporate procedures. As to any facts
material to the opinions expressed herein that we did not independently
establish or verify, we have relied upon the aforesaid agreements, instruments,
certificates, documents and records and upon statements and certificates of
officers and other representatives of the Company and others and of public
officials.

      With your permission, for purposes of the opinion expressed herein, we
have assumed that the Trustee has the power and authority to authenticate the
certificates representing the Securities.

      Based upon and subject to the foregoing, and subject to the further
limitations, qualifications and assumptions stated herein, we are of the opinion
that the issuance of the Securities has been duly authorized by the Company,
each certificate representing the Securities has been duly executed and
delivered by the Company, and, when the certificates representing Securities
have been authenticated and delivered by the Trustee in accordance with the
terms of the Indenture and the Securities have been delivered by the Company to
the Underwriters against payment therefor in accordance with the terms of the
Underwriting Agreement, the Pricing Agreement and the Indenture, the Securities



December 21, 2006
Page 3


will constitute valid and legally binding obligations of the Company and will be
enforceable against the Company in accordance with their terms.

      The opinion expressed herein is subject to the effects of (i) bankruptcy,
insolvency, reorganization, fraudulent conveyance, moratorium and other similar
laws now or hereafter in effect affecting creditors' rights generally; (ii)
general principles of equity (regardless of whether such principles are
considered in a proceeding in law or equity) and (iii) an implied covenant of
good faith, reasonableness and fair dealing, and standards of materiality.

      We express no opinion as to the effect of any Federal or state laws
regarding fraudulent transfers or conveyances. We express no opinion as to the
laws of any jurisdiction other than the laws of the State of New York, the
General Corporation Law of the State of Delaware and the Federal laws of the
United States. In particular (and without limiting the generality of the
foregoing), we express no opinion concerning the effect, if any, of any law of
any jurisdiction (except the State of New York) in which any holder of any
Securities is located that limits the rate of interest that such holder may
charge or collect. Furthermore, we express no opinion as to: (i) whether a
United States Federal court would accept jurisdiction in any dispute, action,
suit or proceeding arising out of or relating to the Securities or the Indenture
or the transactions contemplated thereby; and (ii) any waiver of inconvenient
forum.

      This opinion letter is rendered as of the date hereof based upon the facts
and law in existence on the date hereof. We assume no obligation to update or
supplement this opinion letter to reflect any circumstances that may come to our
attention after the date hereof with respect to the opinion and statements set
forth above, including any changes in applicable law that may occur after the
date hereof.

      We consent to the filing of this opinion letter as an exhibit to the
Company's Current Report on Form 8-K to be filed in connection with the issuance
and sale of the Securities, which will be incorporated by reference into the
Registration Statement and the Prospectus and to the use of our name under the
caption "Legal Opinions" contained in the Prospectus. In giving our consent, we
do not thereby concede that we come within the category of persons whose consent
is required by the Act or the General Rules and Regulations promulgated
thereunder.

                                     Very truly yours,



                                     /s/ LeBoeuf, Lamb, Greene & MacRae LLP