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                                                                     EXHIBIT 5.1
(214) 969-1363

                               October 24, 1997


Encore Wire Corporation
1410 Millwood Road
McKinney, Texas  75069

Dear Sirs:

        We have acted as counsel for Encore Wire Corporation, a Delaware
corporation (the "Company"), in connection with the registration under the
Securities Act of 1933, as amended (the "Securities Act"), of an additional
150,000 shares (the "Shares") of Common Stock, par value $.01 per share, of the
Company for issuance pursuant to the Company's 1989 Stock Option Plan (the
"Plan").

        In connection with the foregoing, we have examined the originals or
copies, certified or otherwise authenticated to our satisfaction, of such
corporate records of the Company, certificates of public officials and of
officers of the Company, and other agreements, instruments and documents as we
have deemed necessary to require as a basis for the opinions hereinafter
expressed.  We are familiar with the corporate proceedings of the Company
relating to the adoption of the Plan and the proposed issuance of the Shares
pursuant to the Plan.  We have also participated in the preparation of the
Company's Registration Statement on Form S-8 (the "Registration Statement") to
be filed with the Securities and Exchange Commission relating to the
registration of the Shares under the Securities Act.

        On the basis of the foregoing, we advise you that in our opinion:

                (1)     The Company is a corporation duly incorporated, validly
        existing and in good standing under the laws of the State of Texas; and 

                (2)     The Shares, when issued and delivered upon the due
        exercise of options duly granted under the Plan, will be legally 
        issued, fully paid and nonassessable.

        We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to all references to us in the Registration
Statement.  The foregoing, however, shall not constitute "consent" to the use
of our name as experts as provided for in Sections 7 and 11 of the Securities
Act or the rules or regulations of the Securities and Exchange Commission
thereunder.

                                          Respectfully submitted,
                                          
                                          THOMPSON & KNIGHT,
                                          A Professional Corporation
                                          
                                          
                                          By: /s/ Jack M. Little  
                                              ----------------------------------
                                              Jack M. Little, Attorney

JML/JER/lrm
