EXHIBIT 5.1

                 [CADWALADER, WICKERSHAM & TAFT LLP LETTERHEAD]

January 11, 2006

Immtech International, Inc.
150 Fairview Drive, Suite 150
Vernon Hills, Illinois 60061

      Re:   Registration Statement on Form S-3

Ladies and Gentlemen:

      We have acted as counsel to Immtech International, Inc., a Delaware
corporation ("Company"), in connection with the preparation and filing of the
Company's Registration Statement on Form S-3 (No. 333-______) ("Registration
Statement") with the Securities and Exchange Commission ("Commission") under the
Securities Act of 1933, as amended ("Securities Act"). The Registration
Statement relates to the offering of 3,744,540 shares of the Company's common
stock, par value $0.01 per share ("Shares"), of which 744,540 Shares are being
offered by certain Selling Stockholders; up to 593,040 Shares are to be issued
upon conversion of Series E Convertible Preferred Stock, $0.01 par value
("Series E Stock") and 151,500 Shares are to be issued upon the exercise of
Common Stock Purchase Warrants. Capitalized terms used herein and not otherwise
defined shall have the meanings thereof set forth in the Registration Statement.

      In rendering the opinion set forth below, we have examined and relied upon
the originals, copies or specimens, certified or otherwise identified to our
satisfaction, of the Registration Statement, as filed on January 11, 2006, with
the Commission under the Securities Act and such other corporate records,
agreements, documents and other instruments and such certificates, corporate and
public records, agreements and instruments and other documents as we have deemed
appropriate as a basis for the opinion set forth below. In such examination we
have assumed the genuineness of all signatures, the authenticity of all
documents, agreements and instruments submitted to us as originals, the
conformity to original documents, agreements and instruments of all documents,
agreements and instruments submitted to us as copies or specimens, the
authenticity of the originals of such documents, agreements and instruments
submitted to us as copies or specimens, the conformity of the text of each
document filed with the Commission through the Commission's Electronic Data
Gathering, Analysis and Retrieval System to the printed document reviewed by us,
and the accuracy of the matters set forth in the documents, agreements and
instruments we reviewed. As to any facts material to such opinion that are not
known to us, we have relied upon statements and representations of officers and
other representatives of the Company and of public officials. Except as
expressly set forth herein, we have not undertaken any independent investigation
(including, without limitation, conducting any review, search or investigation
of any public files, records or dockets) to determine the existence or absence
of the facts that are material to our opinion, and no inference as to our
knowledge concerning such facts should be drawn from our reliance on the
representations of the Company and others in connection with the preparation and
delivery of this letter.

      We have also assumed that all documents, agreements and instruments we
have reviewed have been duly authorized, executed and delivered by all parties
thereto, that such parties had the power and legal right to execute and deliver
such documents, agreements and instruments, and that such documents, agreements
and instruments are valid and binding obligations of such parties, enforceable
in accordance with their terms. As used herein, "to our knowledge," "known to
us" or words of similar import mean the actual knowledge, without independent
investigation, of any lawyer in our firm actively involved in the transactions
contemplated in the Registration Statement.

      We express no opinion concerning the laws of any jurisdiction other than
the State of New York and, to the extent expressly referred to in this opinion
letter, the federal securities laws of the United States of America, and with
respect to the opinion regarding the Shares, the General Corporation Law of the
State of Delaware. While we are not licensed to practice law in the State of
Delaware, we have reviewed applicable provisions of the Delaware General
Corporation Law as we have deemed appropriate in connection with the opinion
expressed herein. Except as described, we have neither examined nor do we
express any opinion with respect to Delaware law.

      Based upon and subject to the foregoing, we are of the opinion that:

      1. the 474,434 Shares to be issued to certain Selling Stockholders upon
conversion of their Series E Stock will, upon issuance in accordance with the
terms of the Company's Certificate of Designation of Series E Stock, be validly
issued, fully-paid and non-assessable;

      2. the 118,606 Shares to be issued to certain Selling Stockholders upon
the exercise of their Series E Stock Purchase Option, and conversion of the
Series E Stock thereby purchased, will, upon such exercise and conversion in
accordance with the terms of the Series E Stock Purchase Options and the Series
E Stock certificate of designation, respectively, including payment in full of
the exercise price therefor, be validly issued, fully paid and non-assessable;
and

      3. the 151,500 Shares to be issued upon the exercise of the Common Stock
Purchase Warrants will, upon exercise in accordance with the terms thereof,
including payment in full of the exercise price therefor, be validly issued,
fully paid and non-assessable.

      This opinion is rendered solely in connection with the registration of the
Shares. It may not be relied upon for any other purpose, or reproduced or filed
publicly by any person, without the written consent of this firm.

      Notwithstanding the foregoing, we hereby consent to the filing of this
opinion as Exhibit 5.1 to the Registration Statement and the amendments thereto
and to the reference to this firm under the caption "Legal Matters" in the
Prospectus which is part of the Registration Statement. In giving this consent,
we do not admit that we are within the category of persons whose consent is
required under Section 7 of the Securities Act, the rules and regulations of the
Commission promulgated thereunder, or Item 509 of Regulation S-K. This opinion
is expressed as of the date hereof unless otherwise expressly stated, and we
disclaim any obligation to update this letter for changes in fact or law or
otherwise.

                                           Sincerely,

                                           /s/ CADWALADER, WICKERSHAM & TAFT LLP