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                                                                     Exhibit 5.1



             [AKIN, GUMP, STRAUSS, HAUER & FELD, L.L.P. LETTERHEAD]

                                November 10, 1999



Century Business Services, Inc.
6480 Rockside Woods Boulevard South
Suite 330
Cleveland, Ohio  44131

Ladies and Gentlemen:

         We have acted as counsel to Century Business Services, Inc., a Delaware
corporation (the "COMPANY"), in connection with the filing of a registration
statement on Form S-3 (the "REGISTRATION STATEMENT") with the Securities and
Exchange Commission pursuant to the Securities Act of 1933, as amended, and the
rules and regulations promulgated thereunder, for the registration of the sale
from time to time of an aggregate of 4,818,626 shares (the "SHARES") of common
stock, par value $0.01 per share ("COMMON STOCK"), of the Company.

         We have, as counsel, examined originals or copies, certified or
otherwise identified to our satisfaction, of such corporate records, agreements,
documents and other instruments, and such certificates or comparable documents
of public officials and of officers and representatives of the Company, and have
made such inquiries of such officers and representatives as we have deemed
relevant and necessary as a basis for the opinion hereinafter set forth.

         In such examination, we have assumed the genuineness of all signatures,
the authenticity of all documents submitted to us as originals, the conformity
to original documents of documents submitted to us as certified or photostatic
copies and the authenticity of the originals of such latter documents. In
addition, we have assumed that the Shares have been issued for at least the par
value thereof. As to all questions of fact material to this opinion that have
not been independently established, we have relied upon certificates or
comparable documents of officers and representatives of the Company.

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AKIN, GUMP, STRAUSS, HAUER & FELD, L.L.P.

Century Business Services, Inc.
November 10, 1999
Page 10

         Based upon such examination and representations, we advise you that, in
our opinion, the Shares have been duly and validly authorized and are validly
issued, fully paid and non-assessable.

         The foregoing opinion is limited to the corporate laws of the State of
Delaware and we express no opinion as to the effect on the matters covered by
this letter of any other law.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement. In addition, we consent to the reference to us under the
caption "Legal Matters" in the prospectus forming a part of the Registration
Statement.

         This opinion is rendered solely to you in connection with the above
matter. This opinion may not be relied upon by you for any other purpose or
relied upon by or furnished to any other person without our prior written
consent.

                                  Sincerely yours,




                                  /S/ AKIN, GUMP, STRAUSS, HAUER & FELD, L.L.P.

                                  AKIN, GUMP, STRAUSS, HAUER & FELD, L.L.P.



