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                                                                     Exhibit 5.1

                        [Letterhead of Dover Corporation]


June 29, 2001

Dover Corporation
280 Park Avenue
New York, NY  10017

        Re:     Form S-8 Registration Statement for Dover Corporation Deferred
                Compensation Plan

Ladies and Gentlemen:

           I am Vice President, General Counsel and Secretary of Dover
Corporation, a Delaware corporation (the "Company"), and, as such, am generally
familiar with its affairs, records, documents and obligations. I am rendering
this opinion in connection with the filing with the Securities and Exchange
Commission (the "Commission") under the Securities Act of 1933, as amended (the
"Securities Act"), of a Registration Statement on Form S-8 (the "Registration
Statement") for the purpose of registering $50 million of Deferred Compensation
Obligations which represent unsecured obligations of the Company to pay deferred
compensation in the future in accordance with the terms of the Dover Corporation
Deferred Compensation Plan (the "Plan").

           I have examined the Registration Statement, the related prospectus,
the Plan and the originals or certified, photostatic or facsimile copies of such
records and other documents as I have deemed relevant and necessary as the basis
for the opinion set forth below. In such examination, I have assumed the legal
capacity of all natural persons, the genuineness of all signatures, the
authenticity of all documents submitted to me as originals, the conformity to
original documents of all documents submitted to me as certified, photostatic or
facsimile copies and the authenticity of the originals of such copies.

           Based upon my examination described above and subject to the
assumptions and qualifications stated herein, I am of the opinion that, when
issued in accordance with the provisions of the Plan, the Deferred Compensation
Obligations will be valid and binding obligations of the Company, enforceable in
accordance with their terms.

           The foregoing opinion is limited to the federal securities laws of
the United States, the General Corporation Law of the State of Delaware and the
laws of the State of New York. The foregoing opinion is also subject to (i)
bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance and
other similar laws now or hereafter in effect relating to or affecting the
rights and remedies of creditors; and (ii) general principles of equity,
including concepts of materiality, reasonableness, conscionability, good faith
and fair dealing.

           I hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the use of my name wherever appearing in the
Registration Statement and any amendment thereto. In giving this consent, I do
not thereby admit that I am within the category of persons whose consent is
required under Section 7 of the Securities Act or the Rules and Regulations of
the Commission promulgated thereunder.

                                                   Very truly yours,


                                                   Robert G. Kuhbach