Exhibit 5


                                                               October 20, 2003

First Tennessee National Corporation
165 Madison Avenue,
Memphis, Tennessee  38103

Gentlemen:

     We have acted as special  securities  counsel for First Tennessee  National
Corporation,  a Tennessee  corporation (the  "Company"),  in connection with the
Company's  Registration  Statement on Form S-8 (the  "Registration  Statement"),
pursuant to the Securities Act of 1933, as amended (the "Act"),  relating to the
First Tennessee National Corporation 2003 Equity Compensation Plan (the "Plan").
This opinion is being  furnished in response to Item 601 of  Regulation  S-K and
the instructions to Form S-8.

     We are familiar with the  proceedings  to date with respect to the Plan and
have examined such records, documents and matters of law and satisfied ourselves
as to such matters of fact as we have  considered  relevant for purposes of this
opinion.

     On the basis of the foregoing, we are of the opinion that the Plan has been
duly and validly  authorized and adopted,  and the securities  being  registered
under the  Registration  Statement that may be issued and sold from time to time
in  accordance  with the Plan have been duly  authorized  for issuance and will,
when issued,  sold and paid for in accordance  with the Plan, be validly issued,
fully paid and non-assessable.

     The  foregoing  opinion is limited to the federal laws of the United States
and the corporate laws of the State of Tennessee,  and we are not expressing any
opinion as to the effect of the laws of any other jurisdiction.

     In rendering  the foregoing  opinion,  we have relied to the extent we deem
such reliance  appropriate as to certain matters on statements,  representations
and other information  obtained from public  officials,  officers of the Company
and other sources believed by us to be responsible.

     We hereby  consent  to the  filing of this  opinion  as an  exhibit  to the
Registration  Statement. In giving such consent, we do not thereby admit that we
are in the category of persons whose consent is required  under Section 7 of the
Act.

                                            Very truly yours,


                                            /s/ Baker, Donelson, Bearman,
                                                Caldwell & Berkowitz, PC
                                            BAKER, DONELSON, BEARMAN,
                                            CALDWELL & BERKOWITZ, PC


                                  Exhibit 5-1