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                                                                    Exhibit 5(a)


                                    September 14, 2000



MBNA Corporation
1100 North King Street
Wilmington, Delaware  19884

Ladies and Gentlemen:

In connection with the registration under the Securities Act of 1993 (the "Act")
of $10,000,000,000 aggregate initial offering price of debt securities ("the
Debt Securities"), preferred stock, par value $.01 per share ("Preferred
Stock"), which may be issued as depositary shares, common stock, par value $.01
per share ("Common Stock"), warrants to purchase Debt Securities, Preferred
Stock, currency or Common Stock, or any combination of the foregoing
("Warrants"), stock purchase contracts, including, without limitation, prepaid
stock purchase contracts ("Stock Purchase Contracts") or as a part of a stock
purchase unit ("Stock Purchase Units"), such Stock Purchase Units to consist of
a Stock Purchase Contract and either Debt Securities or debt obligations of
third parties (including U.S. Treasury Securities) securing the holder's
obligation to purchase Common Stock, and trust preferred securities, I, as Chief
Counsel of MBNA Corporation (the "Company"), have examined such corporate
records, certificates and other documents, and such questions of law, as I have
considered necessary or appropriate for purposes of this opinion. Each
capitalized term used herein, unless otherwise defined herein, has the meaning
ascribed to it in the Registration Statement filed with the Securities and
Exchange Commission as of the date hereof (as amended or supplemented the
"Registration Statement").

I am admitted to the Bar of the State of Maryland and express no opinion as to
the law of any jurisdiction other than the laws of the United States of America
and the State of Maryland. For the purpose of giving the opinion set forth
below, I have assumed the following with respect to each sale of Debt
Securities, Preferred Stock, Depository Shares, Common Stock, Warrants, Stock
Purchase Contracts and Stock Purchase Units: (i) that each sale will be pursuant
to the terms and conditions as contemplated in the Registration Statement, which
has become and remains effective under the Act; (ii) that all necessary Company
actions, approvals and authorizations will have been taken or obtained, and that
such actions will be in conformity with applicable law; (iii) that all necessary
filings and approvals with any regulatory authority will have been made or
obtained, including, without limitation, the fixing of terms with respect to any
security, and that such actions will be in conformity with applicable law; (iv)
that any actions, approvals or authorizations required by any applicable
indenture will have been taken or
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September 14, 2000
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obtained; (v) that the required consideration will have been received by the
Company and (vi) that all parties, other than the Company, will have taken or
obtained any and all necessary actions, authorizations and approvals, that such
parties will be in conformity with applicable law and that any document executed
and delivered by such parties will be enforceable against such parties.

Upon the basis of such examination, it is my opinion that:

(i)   The Preferred Stock and the Common Stock, when authorized and sold as
      contemplated in the Registration Statement, will be duly authorized,
      validly issued, fully paid and non-assessable; and

(ii)  The Debt Securities, Warrants, Stock Purchase Contracts and Stock Purchase
      Units, when authorized and sold as contemplated in the Registration
      Statement, will constitute valid and legally binding obligations of the
      Company, enforceable in accordance with their terms, subject to
      bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium
      and similar laws of general applicability relating to or affecting
      creditors' rights and to general equity principles.

I consent to the filing of this opinion as an exhibit to the Registration
Statement and to the references to me under the heading "Validity of Securities"
in the Prospectus. In giving such consent, I do not thereby admit that I am in
the category of persons whose consent is required under Section 7 of the Act.

                                    Very truly yours,

                                    /s/ John W. Scheflen

                                    John W. Scheflen