Exhibit 5

                                                                  (804) 343-4089
                                                                        2994.027






                             January 7, 1999




F&M National Corporation
9 Court Square
Post Office Box 2800
Winchester, Virginia 22604

Ladies and Gentlemen:

      We  have  acted  as  counsel  to  F&M  National  Corporation,  a  Virginia
corporation  (the  "Company"),   in  connection  with  the  preparation  of  the
Registration Statement on Form S-4 of the Company (the "Registration Statement")
filed with the Securities and Exchange Commission (the  "Commission"),  relating
to  the  registration  under  the  Securities  Act  of  1933,  as  amended  (the
"Securities  Act"),  of a maximum of  675,000  shares (the "Shares") of the
Company's  common  stock,  par value $2.00 per share,  issuable  pursuant to the
Agreement  and Plan of  Reorganization,  dated as of November 25,  1998,  by and
among the Company,  F&M  Bank-Northern  Virginia and Security  Bank  Corporation
("SBC"), and the related Plan of Merger (collectively, the "Agreement"), whereby
each share of SBC common stock,  par value $5.00 per share ("SBC Common Stock"),
will be exchanged for shares of Company  common stock  pursuant to the terms set
forth in the Agreement.

      In connection with this opinion,  we have considered such questions of law
as we have deemed  necessary as a basis for the opinions set forth below, and we
have examined and are familiar with originals or copies,  certified or otherwise
identified  to  our  satisfaction,   of  the  following:  (i)  the  Registration
Statement;  (ii) the Articles of  Incorporation  and By-laws of the Company,  as
amended and as currently in effect;  (iii) certain  resolutions  of the Board of
Directors  of the Company  relating to the  issuance of the Shares and the other
transactions contemplated by the Registration Statement; (iv) the Agreement; and
(v) such other  documents as we have deemed  necessary or appropriate as a basis
for the  opinion  set forth  below.  In our  examination,  we have  assumed  the
genuineness of all signatures, the authenticity of all documents submitted to us
as originals, the conformity to original documents of all documents submitted to
us as certified or photostatic  copies and the  authenticity of the originals of
such  copies.  As to any  facts  material  to  this  opinion  that  we  did  not
independently   establish  or  verify,   we  have  relied  upon  statements  and
representations of officers and other representatives of the Company and others.

      Based upon the foregoing, we are of the opinion that if and when issued in
exchange for shares of SBC Common Stock  pursuant to the terms of the  Agreement
and under the  circumstances  contemplated by the  Registration  Statement,  the
Shares will be validly issued, fully paid and non-assessable.




      The law  covered by the  opinion set forth above is limited to the laws of
the  Commonwealth  of  Virginia  and the  federal  law of the  United  States of
America.

      We hereby  consent to the filing of this  opinion with the  Commission  as
Exhibit 5 to the  Registration  Statement and to the reference to our name under
the caption  "Legal  Matters" in the Proxy  Statement/Prospectus  constituting a
part of the Registration Statement.


                                    Sincerely,

                                    LECLAIR RYAN
                                    A Professional Corporation



                                    By: /s/George P. Whitley
                                        --------------------
                                        George P. Whitley
                                        Vice President

GPW/lsr