EXHIBIT 99.1


FOR IMMEDIATE RELEASE                                      CONTACT: LES VAN DYKE
                                                    DIRECTOR, INVESTOR RELATIONS
                                                                  (281) 492-5370


                    DIAMOND OFFSHORE DRILLING, INC. ANNOUNCES
                RESULTS OF OFFER TO PURCHASE DEBENTURES DUE 2020

Houston, TX--June 7, 2005--Diamond Offshore Drilling, Inc. (NYSE: DO) today
announced the results of its offer to purchase its Zero Coupon Convertible
Debentures due 2020 (the "Securities"). The holders' option to surrender their
Securities for purchase expired at 5:00 p.m., New York City time, on June 6,
2005.

Diamond Offshore has been advised by the paying agent, JPMorgan Chase Bank,
N.A., that $774,110,000 in aggregate principal amount at maturity of the
Securities, which represents over 96% of the outstanding Securities, were
validly surrendered for purchase and not withdrawn. Diamond Offshore has
purchased all of such Securities. The purchase price for the Securities was
$594.25 per $1,000 principal amount at maturity. The aggregate purchase price
for all of the Securities validly surrendered for purchase and not withdrawn was
$460,014,867.50, which Diamond Offshore funded with cash on hand.

Diamond Offshore provides contract drilling services to the energy industry
around the globe and is a leader in deepwater drilling. The Company's fleet of
45 offshore drilling rigs consists of 30 semisubmersibles, 14 jack-ups and one
drillship.

Statements in this press release may contain "forward-looking statements" within
the meaning of Section 27A of the Securities Act of 1933, as amended, and
Section 21E of the Securities Exchange Act of 1934, as amended. Such statements
are inherently subject to a variety of risks and uncertainties that could cause
actual results to differ materially from those anticipated or projected. A
discussion of risk factors that could impact these areas and the Company's
overall business and financial performance can be found in the Company's reports
and other filings with the Securities and Exchange Commission. These factors
include, among others, general economic and business conditions, casualty
losses, industry fleet capacity, changes in foreign and domestic oil and gas
exploration and production activity, competition, changes in foreign, political,
social and economic conditions, regulatory initiatives and compliance with
governmental regulations, customer preferences and various other matters, many
of which are beyond the Company's control. Given these concerns, investors and
analysts should not place undue reliance on forward-looking statements. Each
forward-looking statement speaks only as of the date of this press release. The
Company expressly disclaims any obligation or undertaking to release publicly
any updates or revisions to any forward-looking statement to reflect any change
in the Company's expectations with regard thereto or any change in events,
conditions or circumstances on which any forward-looking statement is based. The
safe harbor for forward-looking statements, however, does not apply to
forward-looking statements made in connection with a tender offer, including
Securities holders' right to surrender Securities for purchase.