EXHIBIT 5.1
 
 
                               January 28, 1997
 
Telegroup, Inc.
2098 Nutmeg Avenue
Fairfield, Iowa 52556
 
  Re: Issuance of Shares of Common Stock by Telegroup, Inc.
 
Ladies and Gentlemen:
   
  We have acted as special counsel to Telegroup, Inc., (the "Company"), in
connection with certain matters arising out of the Company's filing pursuant
to the Securities Act of 1933, as amended (the "Act"), of a registration
statement on Form S-1, File No. 333-42965 (the "Registration Statement"),
relating to the possible sale of up to 3,010,750 shares of common stock (the
"Common Stock") by certain shareholders of the Company pursuant to the
conversion of certain convertible subordinated notes. You have requested our
opinion as to certain matters with respect to the issuance of the Common
Stock.     
 
  We have examined such corporate records of the Company, including its Second
Restated Articles of Incorporation and its Amended and Restated Bylaws
approved by the Board of Directors and stockholders effective upon
consummation of the Company's public offering, and resolutions of the Board of
Directors and stockholders of the Company as well as such other documents as
we deem necessary for rendering the opinion hereinafter expressed.
 
  On the basis of the foregoing, we are of the opinion that the Common Stock
has been duly authorized by the Board of Directors of the Company and the
Company's stockholders, and when issued and sold as described in the
Registration Statement, the Common Stock 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 the use of the name of our firm therein under
the caption "Legal Matters" in the Prospectus filed as a part of the
Registration Statement.
 
                                          Sincerely yours,
 
                                          Marcus & Thompson, P.C.
   
                                                    
                                          By:     /s/ Jay Marcus      
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