This filing is made pursuant to
                                             Rule 424(b)(3) under the Securities
                                             Act of 1933 in connection with
                                             Registration No. 333-71896.



        PROSPECTUS SUPPLEMENT NO. 13 TO PROSPECTUS DATED JANUARY 15, 2002

                   LABORATORY CORPORATION OF AMERICA HOLDINGS

                                  $744,000,000
 Aggregate Principal Amount at Maturity of Liquid Yield Option(TM)Notes due 2021
                          (Zero Coupon - Subordinated)
                                       and
         Common Stock issuable upon Conversion or Purchase of the LYONs


     This prospectus supplement will be used by the holders of LYONs listed
below to resell their LYONs or the shares of our common stock, par value $0.10
per share, issuable upon conversion or purchase of the LYONs.

     You should read this prospectus supplement together with the prospectus
dated January 15, 2002, which is to be delivered with this prospectus
supplement.

     The table below sets forth additional and updated information concerning
beneficial ownership of the LYONs, and supplements and, to the extent
inconsistent with, amends the table appearing under the caption "Selling
Securityholders" beginning on page 37 of the prospectus. To the extent that a
selling securityholder is listed both in the table below and in the table
appearing in the prospectus, the information set forth below regarding that
selling securityholder supersedes the information set forth in the prospectus.
We have prepared this table based on information given to us by the selling
securityholders listed below prior to the date hereof.





                                                   Aggregate       Percentage of      Number of      Percentage of
                                                Principal Amount       LYONs          Shares of       Common Stock
                                                 at Maturity of     Outstanding      Common Stock     Outstanding
                                                LYONs Owned and     Prior to the    Owned and that    Prior to the
Name                                            that May be Sold      Offering     May be Sold (1)    Offering (2)
--------------------------                      ----------------   -------------   ---------------    ------------
                                                                                           
Susquehanna Capital Group                          $36,000,000          4.84%          241,394              *




----------
* Less than 1%.

(1)  Assumes conversion of all of the holder's LYONs at a conversion rate of
     6.7054 shares of common stock per $1,000 principal amount at maturity of
     the LYONs. This conversion rate is subject to adjustment, however, as
     described under "Description of LYONs--Conversion Rights--Conversion
     Adjustments and Delivery of Common Stock" beginning on page 16 of the
     prospectus. As a result, the number of shares of common stock issuable upon
     conversion of the LYONs may increase or decrease in the future.

(2)  Calculated based on Rule 13d-3(d)(1)(i) of the Exchange Act using
     71,267,623 shares of common stock outstanding as of March 29, 2002. In
     calculating this amount for each holder, we treated as outstanding the
     number of shares of common stock issuable upon conversion of all of that
     holder's LYONs, but we did not assume conversion of any other holder's
     LYONs.


     Investing in the LYONs involves risks that are described in "Risk Factors
Relating to the LYONs" beginning on page 8 of the prospectus.

     Neither the Securities and Exchange Commission nor any state securities
commission has approved or disapproved these securities, or determined if this
prospectus is truthful or complete. Any representation to the contrary is a
criminal offense.


            The date of this prospectus supplement is April 26, 2002


(TM)Trademark of Merrill Lynch & Co., Inc.