EXHIBIT 5

January 31, 2005

CMS Energy Corporation
One Energy Plaza
Jackson, MI 49201

Ladies and Gentlemen:

      I am the Assistant General Counsel of CMS Energy Corporation, a Michigan
corporation, (the "Company") and have acted as counsel to the Company in
connection with the Pre-Effective Amendment to the Registration Statement on
Form S-3 (Registration No. 333-119255) (the "Registration Statement") being
filed by the Company with the Securities and Exchange Commission (the
"Commission") under the Securities Act of 1933, as amended (the "Securities
Act"), relating to the registration of the resale of (i) $150 million of 3.375%
Convertible Senior Notes due 2023, Series B (the "Notes") issued under the
Indenture dated as of September 15, 1992, between the Company and JPMorgan Trust
Company N.A. (ultimate successor to NBD Bank, National Association) (the
"Trustee"), as supplemented by the Sixteenth Supplemental Indenture dated as of
December 16, 2004 (collectively, the "Indenture") and (ii) shares of the
Company's common stock (the "Common Stock"), issuable upon conversion of the
Notes, plus such indeterminate number of shares of Common Stock as may become
issuable by means of an adjustment to the conversion rate of the Notes
(collectively, the "Conversion Shares'). The Notes and Conversion Shares are
being registered for selling securityholders pursuant to the terms of a
registration rights agreement dated as of July 16, 2003 between the Company and
the initial purchasers of the Notes. Capitalized terms not otherwise defined
herein have the respective meanings specified in the Registration Statement.

      In rendering this opinion, I have examined and relied upon a copy of the
Registration Statement. I have also examined, or have arranged for the
examination by an attorney or attorneys under my general supervision, originals,
or copies of originals certified to my satisfaction, of such agreements,
documents, certificates and any statements of governmental officials and other
instruments, and have examined such questions of law and have satisfied myself
as to such matters of fact, as I have considered relevant and necessary as a
basis for this opinion. I have assumed the authenticity of all documents
submitted to me as originals, the genuineness of all signatures, the legal
capacity of all natural persons and the conformity with the original documents
of any copies thereof submitted to me, for examination.

      Based on the foregoing it is my opinion that:

      1.    The Company is duly incorporated and validly existing under the laws
            of the State of Michigan.



      2.    The Company has the corporate power and authority to authorize and
            deliver the Notes pursuant to the Indenture and the Conversion
            Shares.

      3.    The Notes are legally issued and binding obligations of the Company,
            enforceable against it in accordance with their terms and entitled
            to the benefits of the Indenture, except that (a) the enforceability
            thereof may be subject to bankruptcy, insolvency, reorganization,
            fraudulent conveyance, moratorium or other similar laws, now or
            hereafter in effect, relating to creditors' rights generally, (b)
            the enforceability thereof is subject to general principles of
            equity (regardless of whether such enforceability is considered in a
            proceeding at law or equity) and that the remedy of specific
            performance and injunctive and other forms of equitable relief may
            be subject to equitable defenses and to the discretion of the court
            before which an proceeding therefore may be brought and (c) certain
            provisions contained in the Indenture and the Notes relating to
            remedies may be limited by public policy, equitable principles or
            other provisions of applicable laws, rules, regulations, court
            decisions or constitutional requirements.

      4.    The Conversion Shares have been duly authorized and, if and when
            issued by the Company upon conversion of the Notes in accordance
            with the terms of the Notes and the Indenture, will be validly
            issued, fully paid and nonassessable.

      For purposes of this opinion, I have assumed that there will be no changes
in the laws currently applicable to the Company and that such laws will be the
only laws applicable to the Company.

      I do not find it necessary for the purposes of this opinion to cover, and
accordingly I express no opinion as to, the application of the securities or
blue sky laws of the various states to the issuance of the Notes and the
Conversion Shares.

      I am a member of the bar of the State of Michigan and I express no opinion
as to the laws of any jurisdiction other than the State of Michigan and the
federal law of the United States of America.

      I hereby consent to the filing of this opinion as an exhibit to the
Company's Registration Statement relating to the resale of the Notes and the
Conversion Shares and to all references to me included in or made a part of the
Registration Statement.

                                                Very truly yours,

                                                /s/ Robert C. Shrosbree
                                                ----------------------------
                                                Robert C. Shrosbree