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                                                                     EXHIBIT 8.1

                       [LETTERHEAD OF BAKER BOTTS L.L.P.]


                                August 27, 2002




Martin Midstream Partners L.P.
4200 Stone Road
Kilgore, Texas 75662

         Re:      Martin Midstream Partners L.P. - Registration Statement on
                  Form S-1

Ladies and Gentlemen:

         We have acted as counsel to Martin Midstream GP LLC (the "General
Partner") and Martin Midstream Partners L.P. (the "Partnership") in connection
with the offer and sale of up to an aggregate of 3,450,000 common units
representing limited partner interests (the "Common Units") in the Partnership
pursuant to a Registration Statement on Form S-1 filed on this date with the
Securities and Exchange Commission (the "Registration Statement"). In connection
therewith, we prepared the discussion set forth under the caption "Material Tax
Consequences" in the Registration Statement (the "Discussion"). Capitalized
terms not defined herein shall have the meanings ascribed to them in the
Registration Statement.

         All statements of legal conclusions contained in the Discussion, unless
otherwise noted, and subject to the qualifications stated therein, are our
opinion with respect to the matters set forth therein as of the effective date
of the Registration Statement. In addition, we are of the opinion that the
federal income tax discussion in the Registration Statement with respect to
those matters as to which no legal conclusions are provided is an accurate
discussion of such federal income tax matters (subject to the qualifications
stated therein and except for the representations and statements of fact of the
Partnership and the General Partner, included in such discussion, as to which we
express no opinion).

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the use of our name in the Registration Statement
under the caption "Material Tax Consequences." This consent does not constitute
an admission that we are within the category of persons whose consent is
required under section 7 of the Securities Act of 1933, as amended, or the rules
and regulations of the Securities Exchange Commission thereunder.

                                                     Very truly yours,

                                                     /s/  Baker Botts L.L.P.


