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                                                               EXHIBIT 8.1     
                       
                    [DAVIS POLK & WARDWELL LETTERHEAD]     
                                  
                               212-450-4606     
                                             
                                          May 6, 1997     
   
Laboratory Corporation of America Holdings     
   
358 South Main Street     
   
Burlington, N.C. 27215     
   
Dear Ladies and Gentlemen:     
   
  We are acting as counsel for Laboratory Corporation of America Holdings, a
Delaware corporation, (the "Company"), in connection with the Registration
Statement on Form S-3, registration no. 333-22427, (including any amendments
thereto, the "Registration Statement"), filed by the Company with the
Securities and Exchange Commission under the Securities Act of 1933, as
amended, for the registration of the Company's (i) transferable subscription
rights (the "Rights"); (ii) Series A Convertible Exchangeable Preferred Stock,
par value $0.10 per share (the "Series A Exchangeable Preferred Stock") and
Series B Convertible Pay-in-Kind Preferred Stock, par value $0.10 per share,
with an aggregate liquidation preference of $828,200,000 (the "Series B PIK
Preferred Stock" and, together with the Series A Exchangeable Preferred Stock,
the "Preferred Stock"); (iii) $250,562,450 aggregate principal amount of
convertible subordinated notes due 2012 (the "Notes") which may be issued in
exchange for the Preferred Stock; and (iv) such currently indeterminate number
of shares of Common Stock, par value $0.01 per share (the "Common Stock") as
may be issuable upon conversion of the Preferred Stock and the Notes.     
   
  We have examined drafts of the Registration Statement, as well as originals
or copies, certified or otherwise identified to our satisfaction, of such
documents, corporate records, certificates of public officials and other
instruments as we have deemed necessary or advisable for purposes of this
opinion.     
   
  We hereby confirm our opinion contained under the heading "Certain Federal
Income Tax Consequences" in the Prospectus contained in the Registration
Statement.     
   
  We are members of the Bar of the State of New York and the opinion set forth
therein is limited to the laws of the State of New York and the federal laws
of the United States of America.     
   
  We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement. We also consent to the reference to us in the
Prospectus contained in the Registration Statement.     
                                             
                                          Very truly yours,     
                                             
                                          /s/ Davis Polk & Wardwell     
