UNITED STATES
                      SECURITIES AND EXCHANGE COMMISSION
                            WASHINGTON, D.C. 20549

                           _________________________

                                   FORM 8-K

                                CURRENT REPORT


               Pursuant to Section 13 or 15(d) of the Securities
                             Exchange Act of 1934

                           _________________________

     Date of Report (date of earliest event reported):  DECEMBER 21, 2005


                              WAUSAU PAPER CORP.
            (Exact name of registrant as specified in its charter)


         WISCONSIN                  1-13923                   39-0690900
      (State or other          (Commission File              (IRS Employer
      jurisdiction of               Number)                 Identification
      incorporation)                                            Number)

                                100 PAPER PLACE
                            MOSINEE, WI 54455-9099
         (Address of principal executive offices, including Zip Code)

                                (715) 693-4470
             (Registrant's telephone number, including area code)


      Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions:

   *  Written communications pursuant to Rule 425 under the Securities Act (17
      CFR 23.425)
   
   *  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17
      CFR 240.14a-12)
   
   *  Pre-commencement communications pursuant to Rule 14d-2(b) under the
      Exchange Act (17 CFR 240.14d-2(b))
   *  Pre-commencement communications pursuant to Rule 13e-4(c) under the
      Exchange Act (17 CFR 240.13e-4(c))

                   INFORMATION TO BE INCLUDED IN THE REPORT


SECTION 7 - REGULATION FD

ITEM 7.01   REGULATION FD DISCLOSURE

      On December 21, 2005, Wausau Paper Corp. issued a news release updating
earnings per share guidance for the fourth quarter.  A copy of the news release
is being furnished as Exhibit 99.1 to this Current Report on Form 8-K and is
incorporated herein by reference.

SECTION 9 - FINANCIAL STATEMENTS AND EXHIBITS

ITEM 9.01   FINANCIAL STATEMENTS AND EXHIBITS

      Exhibit 99.1 News release dated December 21, 2005



                                  SIGNATURES


      Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.

                                    WAUSAU PAPER CORP.



Date:  December 21, 2005            By:    SCOTT P. DOESCHER             
                                           Scott P. Doescher
                                           Senior Vice President-Finance
                                       -2-
                                 EXHIBIT INDEX
                                      TO
                                   FORM 8-K
                                      OF
                              WAUSAU PAPER CORP.
                            DATED DECEMBER 21, 2005
                 Pursuant to Section 102(d) of Regulation S-T
                        (17 C.F.R. Section 232.102(d))



EXHIBIT 99.1 NEWS RELEASE DATED DECEMBER 21, 2005
                                       -3-