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                                                                   EXHIBIT 5.1

                                                              November 5, 2001



Messer Griesheim Holding AG
Frankfurt Airport Center 1, C9
60547 Frankfurt am Main
Germany

         RE:      OFFER TO EXCHANGE UP TO E550,000,000 AGGREGATE PRINCIPAL
                  AMOUNT OF 10.375% SENIOR NOTES DUE 2011

Ladies and Gentlemen:

         We have acted as your special United States counsel in connection with
the filing by Messer Griesheim Holding AG (the "COMPANY") of a registration
statement on Form F-4 (the "REGISTRATION STATEMENT") with the Securities and
Exchange Commission (the "COMMISSION") for the purpose of registering the
issuance of up to E550,000,000 aggregate principal amount of 10.375% Senior
Notes due 2011 (the "EXCHANGE NOTES") under the Securities Act of 1933, as
amended.

         The relevant Exchange Notes are to be issued in exchange for an equal
aggregate principal amount of the Company's outstanding 10.375% Senior Notes due
2011 (the "ORIGINAL NOTES") pursuant to a registration rights agreement among
the Company and Goldman Sachs International dated May 16, 2001 (the
"REGISTRATION RIGHTS AGREEMENT"). The Registration Rights Agreement is filed as
exhibit 4.3 to the Registration Statement.

         The Exchange Notes are to be issued pursuant to the terms of an
indenture between the Company and The Bank of New York, as trustee, dated May
16, 2001 (the "INDENTURE"). The Indenture is filed as exhibit 4.1 to the
Registration Statement. The Indenture is to be qualified under the Trust
Indenture Act of 1939, as amended (the "TRUST INDENTURE ACT"). Capitalized terms
used herein and not otherwise defined shall have the meanings set forth in the
Indenture.

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         In rendering the opinion expressed below, we have examined an executed
copy of the Indenture. We also have examined originals, or copies certified to
our satisfaction, of such corporate records of the Company, agreements and other
instruments, certificates of public officials, certificates of officers and
representatives of the Company and other documents as we have deemed necessary
as a basis for the opinions hereinafter expressed. As to various questions of
fact material to such opinions, we have, when relevant facts were not
independently established, relied upon certifications by officers of the Company
and public officials and representations and warranties made in or pursuant to
the Indenture by the parties thereto as to matters of fact.

         In rendering the opinion expressed below, we have assumed, without
independent verification, that:

         (a) the signatures of persons signing all documents in connection with
which this opinion is rendered are genuine and authorized;

         (b) all documents submitted to us as originals or duplicate originals
are authentic;

         (c) all documents submitted to us as copies, whether certified or not,
conform to original documents and such originals are authentic;

         (d) all parties to the documents reviewed by us are duly organized and
validly existing and have full power and authority to execute, deliver and
perform their obligations under such documents, that all such documents have
been duly authorized by all necessary action on the part of the parties thereto,
and that such documents have been duly executed and delivered by such parties;
and

         (e) any documents referred to herein and executed by the Company have
been duly authorized, executed and delivered pursuant to German law.

         Based upon and subject to the foregoing and subject also to the
comments and qualifications set forth below, and having considered such
questions of law as we have deemed necessary as a basis for the opinion
expressed below, we are of the opinion that:

         When (i) the Registration Statement has been declared effective, (ii)
the Indenture has been duly qualified under the Trust Indenture Act and (iii)
the Exchange Notes have been duly executed by the Company and authenticated in
accordance with the provisions of the Indenture and issued and delivered against
exchange of the Original Notes in accordance with the terms set forth in the
prospectus included as part of the Registration Statement, the Exchange Notes
will be valid and binding obligations of the Company, enforceable against the
Company in accordance with their terms except as: (a) may be limited by
bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance or
transfer or similar laws relating to or affecting creditors' rights generally;
(b) the enforceability thereof is subject to the application of general
principles of equity (regardless of whether considered in a proceeding in equity
or at law), including (x) the


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possible unavailability of specific performance, injunctive relief or any other
equitable remedy and (y) concepts of materiality, reasonableness, good faith and
fair dealing.

         We express no opinion as to (i) any provision in any document referred
to herein providing for the severability of provisions contained therein, (ii)
whether a Federal or state court outside of the State of New York would give
effect to the choice of New York law provided for in any of the documents
referred to herein, (iii) the subject matter jurisdiction of the District Courts
of the United States of America to adjudicate any controversy relating to any
document referred to herein, (iv) possible judicial action giving effect to
foreign governmental actions or foreign laws and (v) the enforceability of
provisions of any document referred to herein to the effect that terms may not
be waived or modified except in writing under limited circumstances.

         We point out with reference to obligations stated to be payable in a
currency other than United States dollars ("DOLLARS") that (i) a New York
statute provides that a judgment rendered by a court of the State of New York in
respect of an obligation denominated in any such other currency would be
rendered in such other currency and would be converted into Dollars at the rate
of exchange prevailing on the date of entry of the judgment and (ii) a judgment
rendered by a Federal court sitting in the State of New York in respect of an
obligation denominated in any such other currency may be expressed in Dollars,
but we express no opinion as to the rate of exchange such Federal court would
apply.

         We express no opinion herein other than as to matters of New York law
and the federal laws of the United States of America. To the extent that the law
of Germany may be relevant to the opinion expressed herein, we have, with your
permission, and without having made any independent investigation with respect
thereto, assumed the correctness of the opinions of Hengeler Mueller, German
counsel to the Company, which opinion has been delivered to you on the date
hereof for filing with the Commission as exhibit 5.2 to the Registration
Statement.

                                                  Very truly yours,

                                        /s/ Milbank, Tweed, Hadley & McCloy LLP

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