Exhibit 5

                               AVENTIS LETTERHEAD

December 2, 2002

Aventis
Strasbourg, France

Re:   Aventis Stock Option Plan 2002

Gentlemen:

I have acted as Head of Corporate Law of Aventis (the "Company") in connection
with the registration with the Securities and Exchange Commission on Form S-8 of
Ordinary Shares, nominal value (euro) 3.82 per share, of the Company (the
"Shares"), that will be issuable upon exercise of options granted under the
above-referenced plan (the "Plan"). In connection with such registration, I have
reviewed the proceedings of the Board of Management of the Company relating to
the registration and proposed issuance of the Shares, the Articles of
Association of the Company and all amendments thereto, and such other documents
and matters as I have deemed necessary to the rendering of the following
opinion.

Based upon that review, it is my opinion that the Shares, when issued in
conformance with the terms and conditions of the Plan, will be legally issued,
fully paid, and nonassessable under the laws of France.

I consent to the use of this opinion in the registration statement filed with
the Securities and Exchange Commission in connection with the registration of
the Shares.

                                           Very truly yours,

                                           /s/  BRUNO ANGRAND
                                           --------------------------------
                                           BRUNO ANGRAND


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