EXHIBIT 5.1
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                    [Letterhead of Elvinger, Hoss & Prussen]

                                                             May 17, 2005




Stolt Offshore S.A.
c/o Stolt Offshore M.S. Ltd.
Dolphin House
Windmill Road
Sunbury-on-Thames
Middlesex, TW16 7HT
England

re Stolt Offshore S.A.
   Registration Statement on Form S-8

Dear Sirs:

     We have acted as counsel to Stolt Offshore S.A., a Luxembourg corporation
(the "Company"), in connection with the registration of 6,310,000 Common Shares,
$2.00 par value, (the "Shares"), issuable pursuant to the Stolt Offshore S.A.
2003 Stock Option Plan ("the Plan") as described in the Registration Statement
on Form S-8 (the "Registration Statement") to be filed by the Company with the
Securities and Exchange Commission pursuant to the Securities Act of 1933, as
amended.

     We have examined the Articles of Incorporation of the Company. We have also
examined the corporate proceedings relating to the authorization and issuance of
the presently outstanding Common Shares and the proposed offer of Shares by the
Company.

     Based upon the foregoing and such further examination and inquiries as we
have deemed necessary, we are of the opinion that:

     1.   The Company is a corporation duly organized and validly existing under
          the laws of Luxembourg.

     2.   The Shares referred to above have been duly authorized for issuance by
          the Company and, when duly issued and the issue price therefor paid as
          set out in the Registration Statement, will be validly issued, fully
          paid and non-assessable Shares of the Company.

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     We hereby consent to the filing of this opinion as an exhibit to the
aforesaid Registration Statement and the inclusion of our name and the advice
attributed to us in the response to Item 6 of the Registration Statement.

     This opinion is strictly limited to the matters stated herein and does not
extend to, and is not to be read as extending by implication to, any other
matters.

     We express no opinion herein with regard to any system of law other than
the laws of Luxembourg as currently applied by the Luxembourg courts and to the
extent that laws other than Luxembourg law may be relevant we have made no
investigation thereof and the opinions expressed herein are subject to the
effect of such laws. In this opinion Luxembourg legal concepts are translated in
English terms and not in their original French terms used in Luxembourg laws.
The concepts concerned may not be identical to the concepts described by the
same English terms as they exist under the laws of other jurisdictions. This
opinion may only be relied upon under the express condition that any issues of
interpretation or any other issues arising thereunder be governed by Luxembourg
law and subject to the exclusive jurisdiction of the Luxembourg Courts.

                                          Very truly yours,

                                          ELVINGER, HOSS & PRUSSEN


                                          By:    /s/ Jean Hoss
                                             ------------------------
                                                   Jean Hoss

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