content: <PAGE>   1
                                                             Registration No. 333-
  
     As filed with the Securities and Exchange Commission on October 24, 1997
  ================================================================================
  
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C.  20549
  
                             ----------------------
  
                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933
  
                             ----------------------
  
                             ENCORE WIRE CORPORATION
             (Exact name of registrant as specified in its charter)
  
              DELAWARE                                      75-2274963
    (State or other jurisdiction              (I.R.S. Employer Identification No.)
  of incorporation or organization)
  
           1410 MILLWOOD ROAD
             MCKINNEY, TEXAS                                   75069
  (Address of Principal Executive Offices)                  (Zip Code)
  
                             ----------------------
  
                   ENCORE WIRE CORPORATION 1989 STOCK OPTION PLAN
                              (Full title of the Plan)
  
                             ----------------------
  
              VINCENT A. REGO                                    COPY TO:
     CHAIRMAN OF THE BOARD, PRESIDENT                         JACK M. LITTLE
        AND CHIEF EXECUTIVE OFFICER                      THOMPSON & KNIGHT, P.C.
          ENCORE WIRE CORPORATION                          1700 PACIFIC AVENUE
            1410 MILLWOOD ROAD                                  SUITE 3300
          MCKINNEY, TEXAS  75069                           DALLAS, TEXAS  75201
  (Name and address of agent for service)                     (214) 969-1363
              (972) 562-9473                     
       (Telephone number, including              
     area code, of agent for service)            
  
                          CALCULATION OF REGISTRATION FEE
  
  <TABLE>
  <CAPTION>
  --------------------------------------------------------------------------------------------------------------
         Title of                                    Proposed          Proposed Maximum           Amount
        Securities              Amount                Maximum              Aggregate                of
           to be                 to be            Offering Price           Offering            Registration
        Registered           Registered(1)         per Share(2)            Price(2)                 Fee
  --------------------------------------------------------------------------------------------------------------
      <S>                       <C>                   <C>                 <C>                     <C>
       Common Stock,            150,000
      par value $.01            shares                $27.50              $4,125,000              $1,250
         per share
  --------------------------------------------------------------------------------------------------------------
  </TABLE>
  
  (1) Pursuant to Rule 416 under the Securities Act of 1933, shares issuable upon
      any stock split, stock dividend or similar transaction with respect to
      these shares are also being registered hereunder.
  
  (2) Estimated solely for the purpose of determining the registration fee
      pursuant to Rule 457(h) on the basis of the average of the high and low
      sales prices of the Common Stock reported in the consolidated reporting
      system for NASDAQ National Market System securities on October 20, 1997.
  <PAGE>   2
                                       PART I
  
                         INCORPORATION OF CONTENTS OF PRIOR
                               REGISTRATION STATEMENT
  
  
      The contents of (i) Registration Statement No. 33-54484 relating to the
  Encore Wire Corporation 1989 Stock Option Plan (the "Plan") filed by the
  Registrant with the Securities and Exchange Commission on November 12, 1992, as
  amended by the Post-Effective Amendment No.1 filed with the Securities and
  Exchange Commission on November 19, 1992 and (ii) Registration Statement No.
  33-89126 relating to the Plan filed by the Registrant with the Securities and
  Exchange Commission on February 2, 1995 (collectively, the "Prior Registration
  Statements") are incorporated herein by reference pursuant to General
  Instruction E to Form S-8.  The purpose of this Registration Statement is to
  register 150,000 additional shares of Common Stock of the Registrant for offer
  and sale pursuant to the Plan.
  
  
                                      PART II
  
                 INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
  
  Item 3.  Incorporation of Documents by Reference.
  
      The following documents filed by the Registrant with the Securities and
  Exchange Commission are incorporated by reference in this Registration
  Statement:
  
      (1)  The Registrant's Annual Report on Form 10-K for the fiscal year ended
           December 31, 1996.
  
      (2)  All other reports filed by the Registrant pursuant to Section 13(a) or
           15(d) of the Securities and Exchange Act since December 31, 1996.
  
      (3)  The description of the Registrant's Common Stock contained in the
           Registration Statement on Form 8-A of the Registrant filed with the
           Securities and Exchange Commission on June 4, 1992 and declared
           effective on July 16, 1992, including any amendment or report filed
           for the purpose of updating such description.
  
      In addition, all documents subsequently filed by the Registrant pursuant to
  Sections 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934,
  prior to the filing of a post-effective amendment which indicates that all
  securities offered pursuant to this Registration Statement have been sold or
  which deregisters all securities then remaining unsold, shall be deemed to be
  incorporated by reference in this Registration Statement and to be a part
  hereof from the date of filing of such documents.
  <PAGE>   3
  Item 8.  Exhibits.
  
      In addition to the exhibits filed with or incorporated by reference in the
  Prior Registration Statements, the following documents are filed or
  incorporated by reference as exhibits to this Registration Statement:
  
  <TABLE>
  <CAPTION>
  Exhibit
  Number          Description
  -------         -----------
  <S>          <C>
  4.1          Encore Wire Corporation 1989 Stock Option Plan, as amended and
               restated in January 1997, and approved by the stockholders on May
               2, 1997.
  
  5.1          Opinion of Thompson & Knight, A Professional Corporation,
               regarding 150,000 shares of Common Stock of the Registrant.
  
  23.1         Consent of Thompson & Knight, A Professional Corporation 
               (contained in its opinion filed herewith as Exhibit 5.1).
  
  23.2         Consent of Ernst & Young LLP, independent auditors.
  
  24.1         Power of Attorney (included on the signature page of this
               Registration Statement).
  </TABLE>
  
  
  
  
                                        -2-
  <PAGE>   4
                                     SIGNATURES
  
      Pursuant to the requirements of the Securities Act of 1933, the Registrant
  certifies that it has reasonable grounds to believe that it meets all of the
  requirements for filing on Form S-8 and has duly caused this Registration
  Statement to be signed on its behalf by the undersigned, thereunto duly
  authorized, in the City of McKinney, State of Texas, on the 23rd day of
  October, 1997.
  
                                     ENCORE WIRE CORPORATION
                                     (Registrant)
                                     
                                     
                                     
                                     By: /s/  Vincent A. Rego
                                         ----------------------------------------
                                             Vincent A. Rego
                                             Chairman of the Board, President
                                             and Chief Executive Officer
  
      Pursuant to the requirements of the Securities Act of 1933, this
  Registration Statement has been signed by the following persons in the
  capacities and on the date indicated.
  
      Each person whose signature appears below constitutes and appoints Vincent
  A. Rego and Scott D. Weaver, and each of them (with full power to each of them
  to act alone), his true and lawful attorney-in-fact and agent, with full power
  of substitution and resubstitution, for him and in his name, place and stead,
  in any and all capacities to sign on his behalf individually and in each
  capacity stated below any amendment, including post-effective amendments, to
  this Registration Statement, and to file the same, with all exhibits thereto
  and other documents in connection therewith, with the Securities and Exchange
  Commission, granting unto said attorneys-in-fact and agents, and each of them,
  full power and authority to do and perform each and every act and thing
  requisite and necessary to be done in and about the premises, as fully to all
  intents and purposes as he might or could do in person, hereby ratifying and
  confirming all that said attorneys-in-fact and agents and either of them, or
  their substitutes, may lawfully do or cause to be done by virtue hereof.
  
  <TABLE>
  <CAPTION>
  Signature                              Title                                              Date
  ---------                              -----                                              ----
  <S>                                    <C>                                                <C>
  /s/ Vincent A. Rego                    Chairman of the Board, President,                  October 23, 1997
  ----------------------------------     Chief Executive Officer and Director                               
  Vincent A. Rego                        (Principal Executive Officer)       
                                                                             
  
  
  /s/ Scott D. Weaver                    Vice President - Finance,                          October 23, 1997
  ----------------------------------     Secretary and Treasurer                                            
  Scott D. Weaver                        (Principal Financial and 
                                         Accounting Officer)      
                                                                  
  </TABLE>
  
  
  
  
  
                                        -3-
  <PAGE>   5
  
  
  <TABLE>
  <S>                                    <C>                                                <C>
  /s/ Donald M. Spurgin                  Director                                           October 23, 1997
  ----------------------------------                                                                        
  Donald M. Spurgin
  
  
  /s/ Donald E. Courtney                 Director                                           October 23, 1997
  ----------------------------------                                                                        
  Donald E. Courtney
  
  
  /s/ Daniel L. Jones                    Director                                           October 23, 1997
  ----------------------------------                                                                        
  Daniel L. Jones
  
  
  /s/ John P. Pringle                    Director                                           October 23, 1997
  ----------------------------------                                                                        
  John P. Pringle
  
  
  /s/ William R. Thomas                  Director                                           October 23, 1997
  ----------------------------------                                                                        
  William R. Thomas
  
  
  /s/ John H. Wilson                     Director                                           October 23, 1997
  ----------------------------------                                                                        
  John H. Wilson
  
  
  /s/ Joseph M. Brito                    Director                                           October 23, 1997
  ----------------------------------                                                                        
  Joseph M. Brito
  </TABLE>
  
  
  
  
  
                                        -4-
  <PAGE>   6
                                 INDEX TO EXHIBITS
  
  
  <TABLE>
  <CAPTION>
        Exhibit
        Number                                        Exhibit
        ------                                        -------
         <S>                <C>
          4.1               Encore Wire Corporation 1989 Stock Option Plan, as amended
                            and restated in January 1997, and approved by the
                            stockholders on May 2, 1997.
         
          5.1               Opinion of Thompson & Knight, A Professional Corporation,
                            regarding 150,000 shares of Common Stock of the Registrant.
         
         23.1               Consent of Thompson & Knight, A Professional Corporation
                            (contained in its opinion filed herewith as Exhibit 5.1).
         
         23.2               Consent of Ernst & Young LLP, independent auditors.
         
         24.1               Power of Attorney (included on the signature page of this
                            Registration Statement).
  </TABLE>
  
  
  
  
  
                                       -5-
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metadata_filer: {"company-data": {"conformed-name": "ENCORE WIRE CORP /DE/", "cik": "0000850460", "assigned-sic": "3350", "irs-number": "762274963", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-38729", "film-number": "97700696"}, "business-address": {"street1": "1410 MILLWOOD ROAD", "street2": "P O BOX 1149", "city": "MCKINNEY", "state": "TX", "zip": "75069", "phone": "2145629473"}, "mail-address": {"street1": "1410 MILLWOOD RD", "street2": "P O BOX 1149", "city": "MCKINNEY", "state": "TX", "zip": "75069"}}
text: 1
                                                             Registration No. 333-
  
     As filed with the Securities and Exchange Commission on October 24, 1997
  ================================================================================
  
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C.  20549
  
                             ----------------------
  
                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933
  
                             ----------------------
  
                             ENCORE WIRE CORPORATION
             (Exact name of registrant as specified in its charter)
  
              DELAWARE                                      75-2274963
    (State or other jurisdiction              (I.R.S. Employer Identification No.)
  of incorporation or organization)
  
           1410 MILLWOOD ROAD
             MCKINNEY, TEXAS                                   75069
  (Address of Principal Executive Offices)                  (Zip Code)
  
                             ----------------------
  
                   ENCORE WIRE CORPORATION 1989 STOCK OPTION PLAN
                              (Full title of the Plan)
  
                             ----------------------
  
              VINCENT A. REGO                                    COPY TO:
     CHAIRMAN OF THE BOARD, PRESIDENT                         JACK M. LITTLE
        AND CHIEF EXECUTIVE OFFICER                      THOMPSON & KNIGHT, P.C.
          ENCORE WIRE CORPORATION                          1700 PACIFIC AVENUE
            1410 MILLWOOD ROAD                                  SUITE 3300
          MCKINNEY, TEXAS  75069                           DALLAS, TEXAS  75201
  (Name and address of agent for service)                     (214) 969-1363
              (972) 562-9473                     
       (Telephone number, including              
     area code, of agent for service)            
  
                          CALCULATION OF REGISTRATION FEE
  --------------------------------------------------------------------------------------------------------------
         Title of                                    Proposed          Proposed Maximum           Amount
        Securities              Amount                Maximum              Aggregate                of
           to be                 to be            Offering Price           Offering            Registration
        Registered           Registered(1)         per Share(2)            Price(2)                 Fee
  --------------------------------------------------------------------------------------------------------------
  Common Stock,            150,000
      par value $.01            shares                $27.50              $4,125,000              $1,250
         per share
  --------------------------------------------------------------------------------------------------------------
  (1) Pursuant to Rule 416 under the Securities Act of 1933, shares issuable upon
      any stock split, stock dividend or similar transaction with respect to
      these shares are also being registered hereunder.
  
  (2) Estimated solely for the purpose of determining the registration fee
      pursuant to Rule 457(h) on the basis of the average of the high and low
      sales prices of the Common Stock reported in the consolidated reporting
      system for NASDAQ National Market System securities on October 20, 1997.
  2
                                       PART I
  
                         INCORPORATION OF CONTENTS OF PRIOR
                               REGISTRATION STATEMENT
  
      The contents of (i) Registration Statement No. 33-54484 relating to the
  Encore Wire Corporation 1989 Stock Option Plan (the "Plan") filed by the
  Registrant with the Securities and Exchange Commission on November 12, 1992, as
  amended by the Post-Effective Amendment No.1 filed with the Securities and
  Exchange Commission on November 19, 1992 and (ii) Registration Statement No.
  33-89126 relating to the Plan filed by the Registrant with the Securities and
  Exchange Commission on February 2, 1995 (collectively, the "Prior Registration
  Statements") are incorporated herein by reference pursuant to General
  Instruction E to Form S-8.  The purpose of this Registration Statement is to
  register 150,000 additional shares of Common Stock of the Registrant for offer
  and sale pursuant to the Plan.
  
                                      PART II
  
                 INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
  
  Item 3.  Incorporation of Documents by Reference.
  
      The following documents filed by the Registrant with the Securities and
  Exchange Commission are incorporated by reference in this Registration
  Statement:
  
      (1)  The Registrant's Annual Report on Form 10-K for the fiscal year ended
           December 31, 1996.
  
      (2)  All other reports filed by the Registrant pursuant to Section 13(a) or
           15(d) of the Securities and Exchange Act since December 31, 1996.
  
      (3)  The description of the Registrant's Common Stock contained in the
           Registration Statement on Form 8-A of the Registrant filed with the
           Securities and Exchange Commission on June 4, 1992 and declared
           effective on July 16, 1992, including any amendment or report filed
           for the purpose of updating such description.
  
      In addition, all documents subsequently filed by the Registrant pursuant to
  Sections 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934,
  prior to the filing of a post-effective amendment which indicates that all
  securities offered pursuant to this Registration Statement have been sold or
  which deregisters all securities then remaining unsold, shall be deemed to be
  incorporated by reference in this Registration Statement and to be a part
  hereof from the date of filing of such documents.
  3
  Item 8.  Exhibits.
  
      In addition to the exhibits filed with or incorporated by reference in the
  Prior Registration Statements, the following documents are filed or
  incorporated by reference as exhibits to this Registration Statement:
  Exhibit
  Number          Description
  -------         -----------
  4.1          Encore Wire Corporation 1989 Stock Option Plan, as amended and
               restated in January 1997, and approved by the stockholders on May
               2, 1997.
  
  5.1          Opinion of Thompson & Knight, A Professional Corporation,
               regarding 150,000 shares of Common Stock of the Registrant.
  
  23.1         Consent of Thompson & Knight, A Professional Corporation 
               (contained in its opinion filed herewith as Exhibit 5.1).
  
  23.2         Consent of Ernst & Young LLP, independent auditors.
  
  24.1         Power of Attorney (included on the signature page of this
               Registration Statement).
  -2-
  4
                                     SIGNATURES
  
      Pursuant to the requirements of the Securities Act of 1933, the Registrant
  certifies that it has reasonable grounds to believe that it meets all of the
  requirements for filing on Form S-8 and has duly caused this Registration
  Statement to be signed on its behalf by the undersigned, thereunto duly
  authorized, in the City of McKinney, State of Texas, on the 23rd day of
  October, 1997.
  
                                     ENCORE WIRE CORPORATION
                                     (Registrant)
                                     
                                     
                                     
                                     By: /s/  Vincent A. Rego
                                         ----------------------------------------
                                             Vincent A. Rego
                                             Chairman of the Board, President
                                             and Chief Executive Officer
  
      Pursuant to the requirements of the Securities Act of 1933, this
  Registration Statement has been signed by the following persons in the
  capacities and on the date indicated.
  
      Each person whose signature appears below constitutes and appoints Vincent
  A. Rego and Scott D. Weaver, and each of them (with full power to each of them
  to act alone), his true and lawful attorney-in-fact and agent, with full power
  of substitution and resubstitution, for him and in his name, place and stead,
  in any and all capacities to sign on his behalf individually and in each
  capacity stated below any amendment, including post-effective amendments, to
  this Registration Statement, and to file the same, with all exhibits thereto
  and other documents in connection therewith, with the Securities and Exchange
  Commission, granting unto said attorneys-in-fact and agents, and each of them,
  full power and authority to do and perform each and every act and thing
  requisite and necessary to be done in and about the premises, as fully to all
  intents and purposes as he might or could do in person, hereby ratifying and
  confirming all that said attorneys-in-fact and agents and either of them, or
  their substitutes, may lawfully do or cause to be done by virtue hereof.
  Signature                              Title                                              Date
  ---------                              -----                                              ----
  /s/ Vincent A. Rego                    Chairman of the Board, President,                  October 23, 1997
  ----------------------------------     Chief Executive Officer and Director                               
  Vincent A. Rego                        (Principal Executive Officer)       
                                                                             
  
  /s/ Scott D. Weaver                    Vice President - Finance,                          October 23, 1997
  ----------------------------------     Secretary and Treasurer                                            
  Scott D. Weaver                        (Principal Financial and 
                                         Accounting Officer)
  -3-
  5
  /s/ Donald M. Spurgin                  Director                                           October 23, 1997
  ----------------------------------                                                                        
  Donald M. Spurgin
  
  /s/ Donald E. Courtney                 Director                                           October 23, 1997
  ----------------------------------                                                                        
  Donald E. Courtney
  
  /s/ Daniel L. Jones                    Director                                           October 23, 1997
  ----------------------------------                                                                        
  Daniel L. Jones
  
  /s/ John P. Pringle                    Director                                           October 23, 1997
  ----------------------------------                                                                        
  John P. Pringle
  
  /s/ William R. Thomas                  Director                                           October 23, 1997
  ----------------------------------                                                                        
  William R. Thomas
  
  /s/ John H. Wilson                     Director                                           October 23, 1997
  ----------------------------------                                                                        
  John H. Wilson
  
  /s/ Joseph M. Brito                    Director                                           October 23, 1997
  ----------------------------------                                                                        
  Joseph M. Brito
  -4-
  6
                                 INDEX TO EXHIBITS
  Exhibit
        Number                                        Exhibit
        ------                                        -------
  4.1               Encore Wire Corporation 1989 Stock Option Plan, as amended
                            and restated in January 1997, and approved by the
                            stockholders on May 2, 1997.
         
          5.1               Opinion of Thompson & Knight, A Professional Corporation,
                            regarding 150,000 shares of Common Stock of the Registrant.
         
         23.1               Consent of Thompson & Knight, A Professional Corporation
                            (contained in its opinion filed herewith as Exhibit 5.1).
         
         23.2               Consent of Ernst & Young LLP, independent auditors.
         
         24.1               Power of Attorney (included on the signature page of this
                            Registration Statement).
  -5-