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                                                                      EXHIBIT 4j


                                 PROMISSORY NOTE

                                  Houston, Texas           April 22, 1999

         ___________________, for value received, promises and agrees to pay on
or before April 22, 2009 unto the order of Rowan Companies, Inc. (hereinafter
called "Payee"), at the offices of the Payee in Houston, Texas in lawful money
of the United States of America, the principal sum of _____________________and
No/100 Dollars ($_______________), together with interest thereon, from and
after the date hereof, on March 31, June 30, September 30 and December 31 of
each year unless such day is not a business day, in which case it shall mean the
immediately succeeding business day, the first such interest payment for the
period beginning on and including the date hereof and ending on and excluding
June 30, 1999, at the per annum interest rate announced publicly by Citibank,
N.A. in New York, New York from time to time as its Base Rate plus 1/2% per
annum; provided, that if any such interest rate shall be lower than the
applicable interest rate for such period determined under Sections 483 and 1274
(d) of the Internal Revenue Code of 1954, as amended (the "Federal Rate"), such
Federal Rate shall apply. The amount of interest payable for any such period is
computed by multiplying the decimal equivalent of the applicable interest rate
for such period by the actual number of days in such period, dividing by 360 and
multiplying the resulting quotient by the principal amount hereof. If the
principal of this Note is prepaid in whole or in part, all accrued and unpaid
interest with respect to such principal amount prepaid is due and payable on the
date of such prepayment.

         Payment of this Note when due is secured by a pledge of and lien on the
Series B Floating Rate Subordinated Convertible Debenture due 2009 of the Payee
dated April 22, 1999 in the principal amount of $______________, issued in the
name of the undersigned, which Debenture, accompanied by an executed transfer
power for such Debenture and in proper form for transfer, has been delivered to
the Payee.

         In the event of the non-payment when due of any liability of the
undersigned to the Payee hereunder, then, or at any time after the happening of
such event, the holder of this Note may, without demand upon or notice to the
undersigned (both of which are expressly waived by the undersigned), declare all
sums owing hereon to be, and such sums shall become, due and payable. Upon such
declaration, the Payee will, to the extent practicable, set off any amounts
owing hereon by the undersigned with amounts owing by the Payee pursuant to the
Series B Floating Rate Subordinated Debenture due 2009. This Note shall be
construed according to and governed by the laws of the State of Texas.


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         By its acceptance hereof, the Payee of this promissory note, hereby
acknowledges and agrees that if (i) Rowan Companies, Inc., a Delaware
corporation (the "Company") fails, at any time, to fulfill its payment
obligations owing in respect of its Series B Floating Rate Subordinated
Convertible Debentures due 2009 (collectively, the "Debentures") or (ii) an
Event of Default (as such term is defined in the Debentures) has occurred and is
continuing, the payment obligations (with respect to principal and interest) of
the undersigned maker of this promissory note under the terms hereof will,
automatically be suspended and terminated until such time, if any, that the
Company has fulfilled all of its payment obligations then due and owing in
respect of the Debentures or such Event of Default no longer exists, as the case
may be.


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