EXHIBIT 5.1



                  [Letterhead of Munger, Tolles & Olson LLP]


                                 May 21, 2001

Berkshire Hathaway Inc.
1440 Kiewit Plaza
Omaha, Nebraska 68131

Ladies and Gentlemen:

     We have acted as counsel to Berkshire Hathaway Inc., a Delaware corporation
("Berkshire") in connection with the preparation of a registration statement on
Form S-3 (the "Registration Statement"), filed with the Securities and Exchange
Commission under the Securities Act of 1933, as amended, covering the
registration of the sale by Berkshire from time to time of up to $700,000,000
maximum aggregate principal amount of debt securities ("Debt Securities").
Berkshire intends to publicly offer and sell the Debt Securities as described in
the Registration Statement.

     For purposes of rendering this opinion, we have made such legal and factual
examinations as we have deemed necessary.  We have examined, among other things,
originals or copies, certified or otherwise identified to our satisfaction, of
such documents, corporate records, certificates of public officials and other
instruments as we have deemed necessary or advisable for purposes of this
opinion.  We have also examined the form indenture (the "Indenture") between
Berkshire and Bank One Trust Company, N.A., as trustee (the "Trustee") pursuant
to which the Debt Securities are to be issued.

     Based upon the foregoing and such other matters of fact and questions of
law as we have deemed necessary, and in reliance thereon, we are of the opinion
that:

     1.  For Debt Securities issued pursuant to the Indenture, when the specific
terms of any particular Debt Security have been duly authorized and established
in accordance with the Indenture, and such Debt Security has been duly
authorized, executed, authenticated, issued and delivered in accordance with the
Indenture, against payment therefor or upon exchange in accordance with the
applicable underwriting or other agreement, such Debt Security will constitute
the valid and binding obligation of Berkshire, subject to bankruptcy,
insolvency, fraudulent transfer, reorganization, moratorium and similar laws of
general applicability relating to or affecting creditors' rights and to general
equitable principles.

     In connection with the opinions expressed above, we have assumed that, at
or prior to the time of delivery of any such Debt Security, (a) Berkshire's
Board of Directors shall have duly established the terms of such Debt Security
and duly authorized the issuance and sale of such Debt Security, in accordance
with Delaware law and such authorization shall not have been modified or
rescinded; (b) the Registration Statement shall have been declared effective and
such


effectiveness shall not have been terminated or rescinded; (c) the Indenture
shall have been duly authorized, executed and delivered by Berkshire in
accordance with applicable law and shall have been qualified under the Trust
Indenture Act of 1939, as amended; (d) the Indenture shall have been duly
authorized, executed and delivered by the Trustee and constitutes the legal,
valid and binding obligation of the Trustee, enforceable against the Trustee in
accordance with its terms and (e) there will not have occurred any change in law
affecting the validity or enforceability of such Debt Security. We have also
assumed that none of the terms of any Debt Security to be established subsequent
to the date hereof, nor the issuance and delivery of such Debt Security, nor the
compliance by Berkshire with the terms of such Debt Security will violate any
applicable law or will result in a violation of any provision of any instrument
or agreement then binding upon Berkshire or any restriction imposed by any court
or governmental body having jurisdiction over Berkshire.

     We are members of the Bar of the State of California and the foregoing
opinion is limited to the laws of the State of California, the General
Corporation Law of the State of Delaware and the federal laws of the United
States of America.  With respect to the Indenture and the Debt Securities which
are stated to be governed by the laws of the State of New York, we have assumed
with your consent that such laws are the same as the laws of the State of
California with respect to the legal, valid and binding nature of the Indenture
and the Debt Securities.

     We hereby consent to the use of this opinion as Exhibit 5.1 to the
Registration Statement and to the reference to our name in the Registration
Statement and the related Prospectus.  In giving such consent, we do not thereby
admit that we are in the category of persons whose consent is required under
Section 7 of the Securities Act of 1933.


                                  Very truly yours,

                                  /s/ MUNGER, TOLLES & OLSON LLP

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