SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549
                             ----------------------

                                    FORM 6-K

                        REPORT OF FOREIGN PRIVATE ISSUER

                    Pursuant to Rule 13a-16 or 15d-16 of the
                         Securities Exchange Act of 1934

                           For the month of May, 2005

                        Commission File Number: 000-16977

                               Stolt-Nielsen S.A.
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                 (Translation of registrant's name into English)



                            c/o Stolt-Nielsen Limited
                                  Aldwych House
                                  71-91 Aldwych
                                 London WC2B 4HN
                                     ENGLAND
                                     -------
                    (Address of principal executive offices)

     Indicate by check mark whether the registrant files or will file annual
reports under cover Form 20-F or Form 40-F.

                        Form 20-F   X             Form 40-F
                                   ---                      ---

     Indicate by check mark if the registrant is submitting the Form 6-K in
paper as permitted by Regulation S-T Rule 101(b)(1): __

     Indicate by check mark if the registrant is submitting the Form 6-K in
paper as permitted by Regulation S-T Rule 101(b)(7): __

     Indicate by check mark whether by furnishing the information contained in
this Form, the registrant is also thereby furnishing the information to the
Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

                        Yes                       No   X
                           ---                        ---

     If "Yes" is marked, indicate below the file number assigned to the
registrant in connection with Rule 12g3-2(b): 82-________

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     In accordance with General Instruction B, attached herewith as Exhibit 99.1
is a press release, dated May 2, 2005, announcing the completion of the Marine
Harvest merger.

     The attached press release shall be deemed to be incorporated by reference
into the prospectuses forming a part of the registrant's Registration Statements
on Form S-8 (No.33-28473, No. 333-6900, No. 333-11178 and No. 333-121315) and to
be a part of such prospectuses from the date of the filing thereof.

     The attached press release contains "forward-looking statements" within the
meaning of Section 27A of the Securities Act of 1933 and Section 21E of the
Securities Exchange Act of 1934. These statements may be identified by the use
of words like "anticipate," "believe," "estimate," "expect," "intend," "may,"
"plan," "project," "will," "should," "seek," and similar expressions. These
statements include statements regarding Stolt-Nielsen S.A.'s future market
environment, outlook, and financing costs. The forward-looking statements
reflect our current views and assumptions and are subject to risks and
uncertainties. The following factors, and others which are discussed in
Stolt-Nielsen S.A.'s public filings and submissions with the U.S. Securities and
Exchange Commission, are among those that may cause actual and future results
and trends to differ materially from our forward-looking statements: the terms,
conditions and amount of Stolt-Nielsen S.A.'s indebtedness; Stolt-Nielsen S.A.'s
ability to comply with its financing agreements; the general economic conditions
and competition in the markets and businesses in which Stolt-Nielsen S.A.
operates; the outcome of legal proceedings; the impact of negative publicity;
environmental challenges and natural conditions facing Stolt-Nielsen S.A.'s
aquaculture business; completion of the 2004 fiscal year audit; the impact of
laws and regulations; uncertainties inherent in operating internationally;
Stolt-Nielsen S.A.'s relationship with significant customers; and operating
hazards, including marine disasters, spills or environmental damage. Many of
these factors are beyond Stolt-Nielsen S.A.'s ability to control or predict.
Given these factors, you should not place undue reliance on the forward-looking
statements. Should one or more of these risks or uncertainties occur, or should
management's assumptions or estimates prove incorrect, actual results and events
may vary materially from those discussed in the forward-looking statements.


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                                    SIGNATURE
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     Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned, thereunto duly authorized.


                                         STOLT-NIELSEN S.A.


Date:    May 2, 2005                 By: /s/ Alan B. Winsor
                                        ----------------------------------------
                                         Name:   Alan B. Winsor
                                         Title:  Attorney-in-Fact


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