Exhibit 5.1

                                 [C H & G LOGO]

                          CALFEE, HALTER & GRISWOLD LLP

                                ATTORNEYS AT LAW

                                September 9, 2003

RPM International Inc.
2628 Pearl Road
P.O. Box 777
Medina, Ohio  44258

         We have acted as counsel for RPM International Inc., a Delaware
corporation (the "Company"), in the preparation of the Registration Statement on
Form S-3 (the "Registration Statement") to be filed with the Securities and
Exchange Commission under the Securities Act of 1933, as amended (the
"Securities Act"), in connection with the shelf registration related to the
offer and sale of (i) 297,000,000 aggregate principal amount of Senior
Convertible Notes due 2033 (the "Notes") issued by the Company on May 13, 2003
and (ii) such indeterminable number of shares of common stock, par value $0.01
per share, of the Company as may be issuable from time to time upon conversion
of the Notes (the "Conversion Shares" and, collectively with the Notes, the
"Securities"). The Notes were issued under that certain Indenture, dated as of
May 13, 2003 (the "Indenture"), between the Company, as issuer, and The Bank of
New York, as trustee (the "Trustee"). The Company issued the Notes pursuant to
that certain Purchase Agreement, dated as of May 8, 2003 (the "Purchase
Agreement"), among the Company, Merrill Lynch, Pierce, Fenner & Smith
Incorporated ("Merrill Lynch") and each of the other Initial Purchasers named in
Schedule A to the Purchase Agreement, for whom Merrill Lynch is acting as
Representative. The Notes and the Conversion Shares are to be offered and sold
by certain securityholders of the Company.

         For purposes of this opinion, we have reviewed such documents, records
and instruments as we have deemed necessary or appropriate for the purposes of
this opinion. In such review, we have assumed the due authorization, execution
and delivery of each document by, and the validity, binding nature and
enforceability of each document against, each of the parties thereto (other than
the Company), the genuineness of all signatures, the legal capacity of natural
persons, the conformity to original documents of all documents submitted to us
as copies (whether or not certified and including facsimiles) and the
authenticity of such latter documents and of all documents submitted to us as
originals. We have also assumed that (i) the Registration Statement shall have
become effective under the Securities Act; (ii) the Trustee (a) is duly
organized, validly existing and in good standing under the laws of its
jurisdiction of organization, (b) is duly qualified to engage in the activities
contemplated by the Indenture, (c) is in compliance, generally and with respect
to acting as a trustee under the Indenture, with all applicable laws and
regulations, and (d) has the requisite organizational and legal power and
authority to perform its obligations under the Indenture; and (iii) the
Indenture shall have become duly qualified under the Trust Indenture Act of
1939, as amended.

         Based upon the foregoing, and subject to the further limitations and
qualifications set forth herein, we are of the opinion that:

         (i)      The Notes have been legally issued and constitute legally
valid and binding obligations of the Company, enforceable against the Company in
accordance with their terms;

         (ii)     The Conversion Shares issuable as of the date hereof have been
duly authorized and reserved and, when delivered upon conversion of the Notes in
accordance with their terms and the terms of the Indenture, will be validly
issued, fully paid and non-assessable.

         We are attorneys licensed to practice law in the State of Ohio. The
opinions expressed herein are limited solely to the Federal Law of the United
States of America, the laws of the State of Ohio and the General Corporation Law
of the State of Delaware. We express no opinion as to the effect or
applicability of the laws of any other jurisdiction except to the extent
hereinafter set forth. Further, we note that each of the Indenture, the Purchase
Agreement and the

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                                                                     Exhibit 5.1

Registration Rights Agreement provides that it shall be governed by the laws of
the State of New York. To the extent that the laws of the State of New York
govern the matters as to which the opinions expressed herein are rendered, you
may rely upon our opinions as opinions with respect to the laws of the State of
New York to the extent that such laws are construed and applied with the same
effect as the substantive laws of the State of Ohio. We express no opinion as to
whether the laws of the State of New York are the same as the laws of the State
of Ohio.

         We consent to the filing of this opinion with the Registration
Statement and to the use of our name therein under the caption "Legal Matters."
Such consent, however, is not an admission that we are in the category of
persons whose consent is required under Section 7 of the Act.

                                           Very truly yours,

                                           CALFEE, HALTER & GRISWOLD LLP

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