EXHIBIT 5.1




                            Eaton and Cottrell, P.A.
                                 Attorney at Law
                            1310 Twenty Fifth Avenue
                        Gulfport, Mississippi 39501-7748
                                  601-864-9900




                                January 28, 1998


Mississippi Power Company
2992 West Beach
Mississippiport, Mississippi  39501

         Re:      Registration Statement on Form S-3

Ladies and Gentlemen:

         We have acted as counsel to Mississippi Power Company (the "Company")
in connection with the preparation of a Registration Statement on Form S-3,
including a preliminary prospectus and preliminary prospectus supplement (the
"Registration Statement"), which is to be filed with the Securities and Exchange
Commission (the "Commission") under the Securities Act of 1933, as amended (the
"Act"), for the registration under the Act of (1) Junior Subordinated Notes (the
"Junior Subordinated Notes") to be issued by the Company, (2) Trust Preferred
Securities to be issued by Mississippi Power Capital Trust II and Mississippi
Power Capital Trust III, (3) the Company's Guarantees (as defined in the
Registration Statement) with respect to such Trust Preferred Securities, and (4)
Senior Notes (the "Senior Notes") to be issued by the Company. The Junior
Subordinated Notes will be issued pursuant to a subordinated note indenture, as
supplemented, between the Company and the trustee named therein (the
"Subordinated Note Indenture"), the Guarantees will be issued pursuant to
separate guaranty agreements between the Company and the trustee named therein
(the "Guaranty Agreements") and the Senior Notes will be issued pursuant to a
senior note indenture, as supplemented, between the Company and the trustee
named therein (the "Senior Note Indenture"), in each case in the respective
forms filed as exhibits to the Registration Statement.

         We are of the opinion that, upon compliance with the pertinent
provisions of the Act, the Trust Indenture Act of 1939, as amended, and the
Public Utility Holding Company Act of 1935, as amended, upon compliance with
applicable securities or blue sky laws of various jurisdictions, upon the
adoption









Mississippi Power Company
January 28, 1998
Page 2








of appropriate resolutions by the Board of Directors of the Company, when the
Junior Subordinated Notes, the Guarantees and the Senior Notes have been issued
and sold, when the Subordinated Note Indenture, the Guaranty Agreement and the
Senior Note Indenture have been duly executed and delivered by the proper
officers of the Company and the trustees named therein, and when the Junior
Subordinated Notes, the Guarantee and the Senior Notes have been executed,
authenticated and delivered in accordance with the terms of the Subordinated
Note Indenture, the Guarantee and the Senior Note Indenture, as the case may be,
the Junior Subordinated Notes, the Guarantee and the Senior Notes will be valid,
binding and legal obligations of the Company (subject to applicable bankruptcy,
moratorium and similar laws from time to time in force and to general principles
of equity, whether considered in a proceeding at law or in equity).

         We also advise you that we have reviewed certain statements in the
Company's Annual Report on Form 10-K for the year ended December 31, 1996, as
indicated under the caption "Experts" in the prospectus, as to matters of law
and legal conclusions and, in our opinion, such statements are correct.

         We hereby consent to the filing of this opinion as an exhibit to the
aforementioned registration statement and to the statements with respect to our
firm under the captions "Legal Matters" and "Experts" in the prospectus.

                                                     Very truly yours,

                                                     /s/Eaton and Cottrell, P.A.

                                                     EATON AND COTTRELL, P.A.