Exhibit 5(a)





                                                     April 11, 2002

American Electric Power Company, Inc.
1 Riverside Plaza
Columbus, Ohio  43215

Ladies and Gentlemen:

                  We have acted as counsel to American Electric Power Company,
Inc. a New York corporation (the "Company"), in connection with the Registration
Statement on Form S-3 (the "Registration Statement") filed by the Company with
the Securities and Exchange Commission (the "Commission") under the Securities
Act of 1933, as amended (the "Act"), relating to (i) Senior Notes; (ii) shares
of Common Stock of the Company, par value $6.50 per share (the "Common Stock");
(iii) Junior Subordinated Debentures ("Junior Subordinated Debentures"); (iv)
Trust Preferred Securities of AEP Capital Trust I, AEP Capital Trust II and AEP
Capital Trust III ("Trust Preferred Securities"); (v)guarantees of the Company
to be issued in connection with the Trust Preferred Securities (the
"Guarantees"); (vi) Stock Purchase Contracts for purchase and sale of Common
Stock (the "Stock Purchase Contracts"); (vii) Stock Purchase Units of the
Company, consisting of (a) a Stock Purchase Contract and (b) a beneficial
interest in Senior Notes, Junior Subordinated Debentures, Trust Preferred
Securities or debt obligations of third parties (including U.S. Treasury
Securities) (the "Stock Purchase Units"); and (viii) Common Stock which may be
issued upon exercise of Stock Purchase Contracts. The Common Stock, the Senior
Notes, the Junior Subordinated Debentures, the Guarantees, the Stock Purchase
Contracts and the Stock Purchase Units are hereinafter referred to collectively
as the "Securities". The Securities may be issued and sold or delivered from
time to time as set forth in the Registration Statement, any amendment thereto,
the prospectus contained therein (the "Prospectus") and supplements to the
Prospectus and pursuant to Rule 415 under the Act for an aggregate initial
offering price not to exceed $3,000,000,000.

                  The Senior Notes will be issued under an Indenture (the
"Senior Indenture") dated as of May 1, 2001 between the Company and The Bank of
New York, as Trustee (the "Senior Trustee"). The Junior Subordinated Debentures
will be issued under an Indenture (the "Subordinated Indenture") between the
Company and The Bank of New York, as Trustee (the "Subordinated Trustee"). The
Senior Indenture and the Subordinated Indenture are hereinafter referred to
collectively as the "Indentures". The Trust Preferred Securities will be issued
under one or more Amended and Restated Trust Agreements (the "Trust Agreement").
The Guarantees will be issued pursuant to one or more Guarantee Agreements (the
"Guarantee Agreement") between the Company and The Bank of New York, as Trustee
(the "Guarantee Trustee"). The Stock Purchase Contracts will be issued pursuant
to a Stock Purchase Contract Agreement (the "Stock Purchase Contract Agreement")
between the Company and The Bank of New York, as Stock Purchase Contract Agent
(the "Stock Purchase Contract Agent").




                                                                               2

                  We have examined the Registration Statement, a form of the
share certificate, the Senior Indenture, the form of the Subordinated Indenture
and the form of Stock Purchase Contract Agreement, which have been filed with
the Commission as exhibits to the Registration Statement. We also have examined
the originals, or duplicates or certified or conformed copies, of such records,
agreements, instruments and other documents and have made such other and further
investigations as we have deemed relevant and necessary in connection with the
opinions expressed herein. As to questions of fact material to this opinion, we
have relied upon certificates of public officials and of officers and
representatives of the Company.

                  In rendering the opinions set forth below, we have assumed the
genuineness of all signatures, the legal capacity of natural persons, the
authenticity of all documents submitted to us as originals, the conformity to
original documents of all documents submitted to us as duplicates or certified
or conformed copies, and the authenticity of the originals of such latter
documents. We also have assumed that: (1) the Senior Indenture is the valid and
legally binding obligation of the Senior Trustee; (2) at the time of execution,
authentication, issuance and delivery of the Junior Subordinated Debentures, the
Subordinated Indenture will be the valid and legally binding obligation of the
Subordinated Trustee; (3) at the time of execution, issuance and delivery of the
Stock Purchase Contracts, the Stock Purchase Contract Agreement will be the
valid and legally binding obligation of the Stock Purchase Contract Agent; (4)
the Guarantee Agreement will be the valid and legally binding obligation of the
Guarantee Trustee; and (5) the Company is validly existing under the laws of New
York. We have assumed further that at the time of execution, authentication,
issuance and delivery of the Junior Subordinate Debentures , the Subordinate
Indenture will have been duly authorized, executed and delivered by the Company.
We have assumed further that at the time of execution, issuance and delivery of
the Stock Purchase Contracts, the Stock Purchase Contract Agreement will have
been duly authorized, executed and delivered by the Company.

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

                  1. With respect to the Common Stock, assuming (a) the taking
by the Board of Directors of the Company of all necessary corporate action to
authorize and approve the issuance of the Common Stock and (b) due issuance and
delivery of the Common Stock, upon payment therefore in accordance with the
applicable definitive underwriting agreement approved by the Board of Directors
of the Company and upon compliance with applicable regulatory requirements, the
Common Stock will be validly issued, fully paid and nonassessable.

                  2. With respect to the Senior Notes and the Junior
Subordinated Debentures, assuming (a) the taking of all necessary corporate
action to approve the issuance and terms of any Senior Notes and the Junior
Subordinated Debentures, the terms of the offering thereof and related matters
by the Board of Directors of the Company, a duly constituted and acting
committee of such Board or duly authorized officers of the Company (such Board
of Directors, committee or authorized officers being referred to herein as the
"Board") and (b) the due execution, authentication, issuance and delivery of
such Senior Notes and the Junior Subordinated Debentures, upon payment of the
consideration therefor provided for in the applicable definitive purchase,
underwriting or similar agreement approved by the Board and otherwise in
accordance with the provisions of the applicable Indenture and such agreement,
such Senior Notes and Junior Subordinated Debentures will




                                                                               3


constitute valid and legally binding obligations of the Company enforceable
against the Company in accordance with their terms.

                  3. With respect to the Guarantees, assuming (a) the taking of
all necessary corporate action to approve the execution and delivery of the
Guarantees in the form filed as an exhibit to the Registration Statement by the
Board of Directors of the Company and (b) the due execution, authentication,
issuance and delivery of the Senior Notes and Junior Subordinated Debentures
underlying such Guarantees, upon payment of the consideration therefore provided
for in the applicable definitive purchase, underwriting or similar agreement
approved by the Board and otherwise in accordance with the provisions of the
applicable Indenture and such agreement and such Guarantees will constitute
valid and legally binding obligations of the Company enforceable against the
Company in accordance with their terms.

                  4. With respect to the Stock Purchase Contracts, assuming (a)
the taking of all necessary corporate action by the Board to approve the
execution and delivery of the Stock Purchase Contract Agreement in the form
filed as an exhibit to the Registration Statement and (b) the due execution,
issuance and delivery of the Stock Purchase Contracts, upon payment of the
consideration for such Stock Purchase Contracts provided for in the applicable
definitive purchase, underwriting or similar agreement approved by the Board and
otherwise in accordance with the provisions of the applicable Stock Purchase
Contract Agreement and such agreement, the Stock Purchase Contracts will
constitute valid and legally binding obligations of the Company enforceable
against the Company in accordance with their terms.

                  5. With respect to the Stock Purchase Units, assuming (a) the
taking of all necessary corporate action by the Board to authorize and approve
(1) the issuance and terms of the Stock Purchase Units, (2) the execution and
delivery of the Stock Purchase Contract Agreement with respect to the Stock
Purchase Contracts which are a component of the Stock Purchase Units in the form
filed as an exhibit to the Registration Statement and (3) the issuance and terms
of the Senior Notes, Junior Subordinated Debentures or Trust Preferred
Securities which are a component of the Stock Purchase Units, the terms of the
offering thereof and related matters and (b) the due execution, authentication,
in the case of such Senior Notes, Junior Subordinated Debentures and Trust
Preferred Securities, issuance and delivery of (1) Stock Purchase Units, (2)
such Stock Purchase Contracts and (3) such Senior Notes, Junior Subordinated
Debentures and Trust Preferred Securities in each case upon the payment of the
consideration therefore provided for in the applicable definitive purchase,
underwriting or similar agreement approved by the Board and in accordance with
the provisions of the applicable Stock Purchase Contract Agreement, in the case
of such Stock Purchase Contracts, and the applicable Indenture, in the case of
such Senior Notes and Junior Subordinated Debentures, and the Trust Agreement,
in the case of the Trust Preferred Securities, such Stock Purchase Units will
constitute valid and legally binding obligations of the Company enforceable
against the Company in accordance with their terms.

                  Our opinions set forth in paragraph 2 through 5 above are
subject to the effects of (i) bankruptcy, insolvency, fraudulent conveyance,
reorganization, moratorium and other similar laws relating to or affecting
creditors' rights generally, (ii) general equitable principles (whether
considered in a proceeding in equity or at law) and (iii) an implied covenant of
good faith and fair dealing.




                                                                               4

                  We are members of the Bar of the State of New York, and we do
not express any opinion herein concerning any law other than the law of the
State of New York and the Federal law of the United States.

                  We hereby consent to the filing of this opinion letter as
Exhibit 5(a) to the Registration Statement and to the use of our name under the
caption "Legal Opinions" in the Prospectus included in the Registration
Statement.

                                            Very truly yours

                                            /s/ Simpson Thacher & Bartlett

                                            SIMPSON THACHER & BARTLETT