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                                                                    EXHIBIT 10.3

THIS NOTE HAS NOT BEEN AND WILL NOT BE REGISTERED UNDER THE UNITED STATES
SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT") AND MAY NOT BE
OFFERED, SOLD, PLEDGED, CONVERTED OR OTHERWISE DISPOSED OF IN THE UNITED STATES
OR TO, OR FOR THE ACCOUNT OR BENEFIT OF, ANY "U.S. PERSON" (AS DEFINED IN
REGULATION S UNDER THE SECURITIES ACT) UNLESS THE NOTE HAS BEEN REGISTERED
UNDER THE SECURITIES ACT AND ANY APPLICABLE STATE SECURITIES OR BLUE SKY LAWS
OR EXEMPTIONS FROM THE REGISTRATION REQUIREMENTS OF SUCH LAWS ARE AVAILABLE.

ANY UNITED STATES PERSON WHO HOLDS THIS OBLIGATION WILL BE SUBJECT TO
LIMITATIONS UNDER THE UNITED STATES INCOME TAX LAWS, INCLUDING THE LIMITATIONS
PROVIDED IN SECTIONS 165(J) AND 1287(A) OF THE UNITED STATES INTERNAL REVENUE
CODE OF 1986, AS AMENDED.

THIS OBLIGATION IS NOT A DEPOSIT AND IS NOT INSURED BY ANY AGENCY OF THE UNITED
STATES GOVERNMENT.


                           HARKEN ENERGY CORPORATION

                     5.5% SENIOR CONVERTIBLE NOTES DUE 2002

                             TEMPORARY GLOBAL NOTE

         Harken Energy Corporation, a Delaware corporation (hereinafter, the
"Issuer," which term includes any successor corporation under the Trust
Indenture hereinafter referred to), for value received, hereby promises to pay
to bearer upon presentation and surrender of this Temporary Global Note (the
"Global Note") the principal sum of Seventy Million United States Dollars (U.S.
$70,000,000) on June 11, 2002, and, to pay interest thereon from the date
hereof, semi- annually in arrears on June 11 and December 11 in each year,
commencing December 11, 1997, at the rate of 5.5% per annum, calculated on the
basis of a 360-day year consisting of twelve 30-day months, until the principal
hereof is paid or payment thereof is duly provided for.

         This Global Note is one of a duly authorized issue of notes designated
as the 5.5% Senior Convertible Notes Due 2002 (the "Notes") of the Issuer
issued and to be issued under the Trust Indenture dated as of June 11, 1997
(herein called the "Trust Indenture"), between the Issuer and Marine Midland
Bank, as Trustee.  It is a temporary security and is exchangeable in whole or
in part without charge for definitive Notes in bearer form, with interest
coupons attached, on or after the end of the Restricted Period, as defined in
the Trust Indenture, as promptly as practicable following presentation of
election by any of the beneficial owner or owners of this Global Note.

         Until exchanged in full for definitive Notes this Global Note shall in
all respects be ratably entitled to the same benefits under, and subject to the
same Terms and Conditions of, the Trust Indenture as definitive Notes
authenticated and delivered thereunder, except that the holder of this Global
Note shall not be entitled to receive payment of principal or interest hereon,
and this Note shall not be convertible into Shares of the Issuer's Common
Stock.

         This Global Note, the definitive Notes and the Trust Indenture shall
be governed by and construed in accordance with the laws of the State of New
York.
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Global Note
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         All terms used in this Global Note which are defined in the Trust
Indenture shall have the respective meanings assigned to them in the Trust
Indenture.

         Unless the certificate of authentication hereon has been executed by
the Trustee or on behalf of the Trustee by the Authenticating Agent by manual
signature of one of its authorized signatories, this Global Note shall not be
entitled to any benefit under the Trust Indenture and shall not be valid or
obligatory for any purpose.

         IN WITNESS WHEREOF, the Issuer has caused this Global Note to be duly
executed in its corporate name by the manual or facsimile signatures of the
undersigned duly authorized officers of the Issuer.

Dated as of June 11, 1997

         HARKEN ENERGY CORPORATION



         By: /s/ LARRY E. CUMMINGS                    
            ----------------------------------------
            Larry E. Cummings, Vice President


[Corporate Seal]

ATTEST:


         By: /s/ GREGORY S. PORTER                            
            ----------------------------------------
            Gregory S. Porter, Assistant Secretary



                    TRUSTEE'S CERTIFICATE OF AUTHENTICATION

         This Global Note is one of the Notes referred to in the within
mentioned Trust Indenture.

                                         MIDLAND BANK PLC
                                         Authenticating Agent for Marine Midland
                                         Bank, as Trustee

                          By:  /s/ CARL BALDARY
                             --------------------------

                          Name:    Carl Baldary           
                               ------------------------

                          Title:   Transaction Manager            
                                -----------------------