Exhibit (d)(xxxix)

AMENDMENT NO. 4
TO
SUBADVISORY AGREEMENT

     This AMENDMENT NO. 4 TO SUBADVISORY AGREEMENT is dated as of October 2, 2007, by and between AIG SUNAMERICA ASSET MANAGEMENT CORP., formerly known as SunAmerica Asset Management Corp., a Delaware corporation (the “Adviser”), and MORGAN STANLEY INVESTMENT MANAGEMENT INC., a Delaware corporation (the “Subadviser”).

W I T N E S S E T H:

     WHEREAS, the Adviser and SunAmerica Series Trust, a Massachusetts business trust (the “Trust”), have entered into an Investment Advisory and Management Agreement dated as of January 1, 1999, as amended from time to time (the “Advisory Agreement”), pursuant to which the Adviser has agreed to provide investment management, advisory and administrative services to the Trust, and pursuant to it which the Adviser may delegate one or more of its duties to a subadviser pursuant to a written subadvisory agreement;

     WHEREAS, the Adviser and the Subadviser are parties to a Subadvisory Agreement dated January 1, 1999, as amended from time to time (the “Subadvisory Agreement”), pursuant to which the Subadviser furnishes investment advisory services to certain series (the “Portfolios”) of the Trust, as listed on Schedule A of the Subadvisory Agreement;

     WHEREAS, the parties desire to amend the Subadvisory Agreement to comply with the requirements of rules 17a-10, 10f-3, 12d3-1 and 17e-1 under the Investment Company Act of 1940, as amended, relating to certain exemptions available for transactions with subadvisory affiliates; and

     WHEREAS, the Board of Trustees of the Trust has approved this Amendment to the Subadvisory Agreement and it is not required to be approved by the shareholders of the Portfolios.

     NOW, THEREFORE, it is hereby agreed between the parties hereto as follows:

1. The following provision is inserted in Section 1 of the Subadvisory Agreement:

“The Subadviser also represents and warrants that in furnishing services hereunder, the Subadviser will not consult with any other subadviser of the Portfolios or other series of the Trust, to the extent any other subadvisers are engaged by the Adviser, or any other subadvisers to other investments companies that are under common control with the Trust, concerning transactions of the Portfolios in securities or other assets, other than for purposes of complying with the conditions of paragraphs (a) and (b) of rule 12d3-1 under the Act.”

2. Counterparts. This Amendment may be executed in two or more counterparts, each of which shall be an original and all of which together shall constitute one instrument.

3. Full Force and Effect. Except as expressly supplemented, amended or consented to hereby, all of the representations, warranties, terms, covenants, and conditions of the Subadvisory Agreement shall remain unchanged and shall continue to be in full force and effect.

4. Miscellaneous. Capitalized terms used but not defined herein shall have the meanings assigned to them in the Subadvisory Agreement.

     IN WITNESS WHEREOF, the parties have caused their respective duly authorized officers to execute this Agreement as of the date first above written.

AIG SUNAMERICA ASSET MANAGEMENT CORP.
By:	/s/ PETER A. HARBECK
Name:	Peter A. Harbeck
Title:	President & CEO

MORGAN STANLEY INVESTMENT MANAGEMENT INC.
By:	/s/ MICHAEL P. KILEY
Name:	Michael P. Kiley
Title:	Managing Director

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