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                                                                     Exhibit 5.2



                     [Letterhead of Pillsbury Winthrop LLP]

                                 April 10, 2003


Union Electric Company
1901 Chouteau Avenue
St. Louis, Missouri 63103


Ladies and Gentlemen:

       Union Electric Company, a Missouri corporation (the "COMPANY"), and Union
Electric Capital Trust I, a Delaware business trust, have filed with the
Securities and Exchange Commission (the "COMMISSION") a Registration Statement
on Form S-3 (Registration Nos. 333-87506 and 333-87506-01) (the "REGISTRATION
STATEMENT") under the Securities Act of 1933, as amended (the "SECURITIES ACT"),
with respect to up to $750,000,000 maximum aggregate offering price of
securities, which was declared effective by the Commission on August 13, 2002.
On April 9, 2003, the Company issued and sold $114,000,000 of its 4.75% Senior
Secured Notes due 2015 (the "NOTES") pursuant to an indenture dated as of August
15, 2002 between the Company and The Bank of New York, as trustee (the
"INDENTURE").

       In connection with the issuance and sale of the Notes by the Company, we
have reviewed originals (or copies certified or otherwise identified to our
satisfaction) of the Registration Statement (including the exhibits thereto),
the Restated Articles of Incorporation and By-Laws of the Company as in effect
on the date hereof, the Indenture, a specimen of the Notes, corporate and other
documents, records and papers and certificates of public officials. In
connection with such review, we have assumed the genuineness of all signatures,
the legal capacity of natural persons, the conformity to the originals of the
documents submitted to us as certified or photostatic copies, the authenticity
of the originals of such documents and all documents submitted to us as
originals and the correctness of all statements of fact contained in such
original documents. We are members of the Bar of the State of New York and, for
purposes of this opinion, do not hold ourselves out as experts on the laws of
any jurisdiction other than the State of New York.

       On the basis of such review, we are of the opinion that the Notes
constitute the valid and binding obligations of the Company, subject to
bankruptcy, insolvency, fraudulent conveyance, reorganization, moratorium and
other similar laws affecting creditors' rights, to general equitable principles
(whether considered in a proceeding in equity or at law) and to an implied
covenant of reasonableness, good faith and fair dealing.

       We hereby consent to the filing of this opinion as an exhibit to the
Company's Current Report on Form 8-K filed on April 10, 2003, which is
incorporated by reference in the Registration Statement. In giving this consent,
we do not thereby admit that we are within the category of persons whose consent
is required under Section 7 of the Securities Act or the rules and regulations
of the Commission thereunder.

                                           Very truly yours,

                                           /s/ Pillsbury Winthrop LLP