Exhibit 5.1

                           [LETTERHEAD OF BROWN & WOOD LLP]



                                   January 5, 1998



Merrill Lynch & Co., Inc.
World Financial Center
North Tower
250 Vesey Street
New York, New York  10281
 

                                          
Merrill Lynch Preferred Funding III, L.P.    Merrill Lynch Preferred Funding IV, L.P.
c/o Merrill Lynch & Co., Inc.                c/o Merrill Lynch & Co., Inc.
World Financial Center                       World Financial Center
North Tower                                  North Tower
250 Vesey Street                             250 Vesey Street
New York, New York  10281                    New York, New York  10281


Merrill Lynch Preferred Capital Trust III    Merrill Lynch Preferred Capital Trust IV
c/o Merrill Lynch & Co., Inc.                c/o Merrill Lynch & Co., Inc.
World Financial Center                       World Financial Center
North Tower                                  North Tower
250 Vesey Street                             250 Vesey Street
New York, New York  10281                    New York, New York  10281

 
Ladies and Gentlemen:

          We have acted as counsel to Merrill Lynch & Co., Inc., a Delaware 
corporation (the "Company"), Merrill Lynch Preferred Funding III, L.P., and 
Merrill Lynch Preferred Funding IV, L.P., Delaware limited partnerships 
(each, a "Partnership"), and Merrill Lynch Preferred Capital Trust III and 
Merrill Lynch Preferred Capital Trust IV, statutory business trusts formed 
under the laws of the State of Delaware (each, a "Trust"), in connection with 
the preparation and filing by the Company, the Partnerships and the Trusts 
with the Securities and Exchange Commission (the "Commission") of a 
Registration Statement on Form S-3 (Registration No. 333-42859) (the 
"Registration Statement") under the Securities Act of 1933, as amended, with 
respect to (i) the guarantee (each, a "Trust Guarantee") to be issued by the 
Company to The Chase Manhattan Bank, as trustee, for the benefit of the 
holders of the Trust Originated Preferred Securities to be issued by each 
Trust (the "Trust Preferred Securities"), (ii) the guarantee (each, a 
"Partnership Guarantee") to be issued by the Company with respect to the 



Partnership Preferred Securities to be issued by each Partnership (the 
"Partnership Preferred Securities"), (iii) the guarantees (the "Investment 
Guarantees") to be issued by the Company for the benefit of the holders of 
the Partnership Preferred Securities with respect to certain debentures (the 
"Debentures") to be issued by one or more of the Company's eligible 
controlled affiliates and (iv) the subordinated debentures (the "Company 
Debentures") to be issued by the Company to the Partnerships pursuant to 
respective indentures (the "Company Indentures") between the Company and The 
Chase Manhattan Bank, as trustee (the "Debenture Trustee"), each in the form 
filed as exhibits to the Registration Statement.  The Trust Guarantees, the 
Partnership Guarantees and the Investment Guarantees are hereinafter 
collectively referred to as the "Guarantees".

          We have reviewed the corporate action of the Company in connection 
with the giving of the Guarantees and the issuance and sale of the Company 
Debentures by the Company and have examined, and have relied as to matters of 
fact upon, originals or copies certified or otherwise identified to our 
satisfaction, of such corporate records, agreements, documents and other 
instruments and such certificates or comparable documents of public officials 
and of officers and representatives of the Company, and have made such other 
and further investigations as we have deemed relevant and necessary as a 
basis for the opinions hereinafter set forth.

          In such examination, we have assumed the genuineness of all 
signatures, the legal capacity of natural persons, the authenticity of all 
documents submitted to us as originals, the conformity to original documents 
of all documents submitted to us certified or photostatic copies, and the 
authenticity of the originals of such latter documents.

          Based upon the foregoing, and subject to the qualifications and 
limitations stated herein, we are of the opinion:

          1.   When a Trust Guarantee has been duly authorized, executed and 
delivered by the Company, and upon the issuance and sale of the related Trust 
Preferred Securities to the holders of the Trust Preferred Securities in 
accordance with the Registration Statement, such Trust Guarantee will 
constitute a valid and legally binding obligation of the Company  enforceable 
against the Company in accordance with its terms.

          2.   When a Partnership Guarantee has been duly authorized, 
executed and delivered by the Company, and upon the issuance and sale of the 
related Partnership Preferred Securities to the holders of the Partnership 
Preferred Securities in accordance with the Registration Statement, such 
Partnership Guarantee will constitute a valid and legally binding obligation 
of the Company enforceable against the Company in accordance with its terms.

          3.   When the Investment Guarantees have been duly authorized, 
executed and delivered by the Company, and upon the issuance and sale of the 
related Debentures to a Partnership in accordance with the Registration 
Statement, such Investment Guarantees will constitute valid and legally 
binding obligations of the Company enforceable against the Company in 
accordance with their terms.

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          4.   When the Company Debenture has been duly authorized, executed 
and issued by the Company and upon the issuance and sale of the Company 
Debentures to a Partnership in accordance with the Registration Statement 
(assuming due authorization, execution and delivery of the Company Indenture 
by the Debenture Trustee and due authentication of the Company Debenture by 
the Debenture Trustee), such Company Debenture will constitute a valid and 
legally binding obligation of the Company enforceable against the Company in 
accordance with its terms.

          With respect to enforcement, the above opinions are qualified to 
the extent that enforcement of the Guarantees or the Company Debentures may 
be limited by bankruptcy, insolvency, reorganization, moratorium or similar 
laws relating to or affecting creditors' rights generally and except as 
enforcement thereof is subject to general equity principles (regardless of 
whether enforcement is considered in a proceeding in equity or at law).

          We consent to the filing of this opinion as an exhibit to the 
Registration Statement and to the use of our name wherever appearing in the 
Registration Statement and any amendment thereto.

                                   Very truly yours,



                                   /s/ Brown & Wood LLP

                           

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