Exhibit 5.1

                       KRAMER LEVIN NAFTALIS & FRANKEL LLP
                                919 THIRD AVENUE
                           NEW YORK, N.Y. 10022 - 3852


TEL (212) 715-9100                                             47, Avenue Hoche
FAX (212) 715-8000                                               75008 Paris
                                                                   France

                                January 31, 2001



Securities and Exchange Commission
Judiciary Plaza
450 Fifth Street, N.W.
Washington, D.C.  20549

                  Re:      Registration Statement on Form S-8

Ladies and Gentlemen:

                  We have acted as corporate counsel to SF Holdings Group, Inc.,
a  Delaware   corporation  (the  "Registrant").   The  Registrant  has  filed  a
Registration  Statement  on Form S-8  (the  "Registration  Statement")  with the
Securities  and  Exchange  Commission  (the  "Commission"),  with respect to the
registration  under the  Securities  Act of 1933, as amended (the "Act"),  of an
aggregate of 95,995  shares (the  "Shares") of Class D common  stock,  par value
$0.001 per share, to be issued pursuant to the Registrant's Share Incentive Plan
(the "Plan").

                  In connection  with the  registration  of the Shares,  we have
reviewed  copies of the  Registration  Statement,  the  Plan,  the  Amended  and
Restated Certificate of Incorporation,  as amended, and the Amended and Restated
By-laws of the  Registrant,  and such  other  documents  and  records as we have
deemed  necessary  to enable us to express an  opinion  on the  matters  covered
hereby.  In rendering this opinion,  we have (a) assumed (i) the  genuineness of
all  signatures on all documents  examined by us, (ii) the  authenticity  of all
documents  submitted to us as originals,  and (iii) the  conformity to authentic
original documents of all documents  submitted to us as photostatic or conformed
copies;  and (b) relied on (i)  certificates of public  officials and (ii) as to
matters of fact,  statements and certificates of officers and representatives of
the Registrant.

                  Based  upon  the  foregoing,  we are of the  opinion  that the
Shares covered by the Registration  Statement,  upon the issuance of such Shares
upon the exercise of options granted  pursuant to the Plan and payment  therefor
in accordance  with the terms of such options and as stated in the Plan and at a
purchase price not less than par value,  will be validly issued,  fully paid and
non-assessable.

                  We hereby  consent to the use of this opinion as an exhibit to
the Registration  Statement.  In giving the foregoing consent, we do not thereby
admit that we are in the  category of persons  whose  consent is required  under
Section 7 of the Act or the rules and regulations of the Commission thereunder.

                  We are  delivering  this  opinion  to the  Registrant,  and no
person other than the Registrant may rely upon it.

                                         Very truly yours,

                                         /s/ Kramer Levin Naftalis & Frankel LLP

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