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                                                                     EXHIBIT 5.1

001166.0393                                           July 8, 1997



Houston Industries Incorporated
Houston Industries Plaza
1111 Louisiana Street
Houston, Texas  77002

Ladies and Gentlemen:

          We have acted as counsel for Houston Industries Incorporated, a Texas
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 "Securities Act"), relating to the proposed issuance
and sale of up to 22,909,040 ___% Automatic Common Exchange Securities (the
"Securities"). The Securities will be issued under an Indenture (the
"Indenture") between the Company and The First National Bank of Chicago, as
Trustee (the "Trustee").

          In our capacity as your counsel in the connection referred to above,
we have examined the Restated Articles of Incorporation and Amended and Restated
Bylaws of the Company, as amended to date, and the forms (filed as exhibits to
the Registration Statement) of the Indenture and the Underwriting Agreement (the
"Underwriting Agreement") to be entered into between the Company and Goldman,
Sachs & Co., Credit Suisse First Boston Corporation and Merrill Lynch, Pierce,
Fenner & Smith Incorporated, as representatives of the several underwriters
named therein (the "Underwriters"), and have examined the originals, or copies
certified or otherwise identified, of corporate records of the Company,
including minute books of the Company as furnished to us by the Company,
certificates of public officials and of representatives of the Company, statutes
and other instruments or documents, as a basis for the opinions hereinafter
expressed. In giving such opinions, we have relied upon certificates of officers
of the Company with respect to the accuracy of the material factual matters
contained in such certificates. In making our examination, we have assumed that
all signatures on documents examined by us are genuine, that all documents
submitted to us as originals are authentic and that all documents submitted to
us as certified or photostatic copies conform with the original copies of such
documents.
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Houston Industries Incorporated       -2-                          July 8, 1997

          On the basis of the foregoing, and subject to the assumptions,
limitations and qualifications set forth herein, we are of the opinion that:

          When (i) the Registration Statement has become effective under the
Securities Act and the Indenture has been qualified under the Trust Indenture
Act of 1939, as amended, (ii) the issuance and sale of the Securities has been
duly authorized by all requisite corporate action on the part of the Company,
(iii) the Indenture and the Underwriting Agreement have been duly authorized,
executed and delivered, and (iv) the Securities have been duly authorized,
executed and authenticated in accordance with the terms of the Indenture and
delivered to and paid for by the Underwriters as contemplated by the
Underwriting Agreement, the Securities will be legal, valid and binding
obligations of the Company enforceable in accordance with their terms, except as
such enforceability is subject to (x) any applicable bankruptcy, insolvency,
reorganization or other laws relating to or affecting creditors' rights
generally and (y) general principles of equity (regardless of whether such
enforceability is considered in a proceeding in equity or at law).

          The opinions set forth above are limited in all respects to matters of
Texas law and the contract law of the State of New York as in effect on the date
hereof. At your request, this opinion is being furnished to you for filing as
Exhibit 5 to the Registration Statement. Additionally, we hereby consent to the
reference to our Firm under the caption "Validity of the Securities" in the
Registration Statement. In giving such consent, we do not thereby concede 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 promulgated
thereunder.

                                      Very truly yours,


                                      BAKER & BOTTS, L.L.P.



MSS/TST