USS Pasig (AW-3) was one of four water distilling ships built for the United States Navy during World War II.

Originally laid down as SS Mission San Xavier, a Maritime Commission T2-SE-A2 tanker (MC hull 1826) by the Marinship Corporation of Sausalito, California on 18 May 1944; renamed USS Pasig (AO–91) on 3 July 1944; launched on 15 July 1944, sponsored by Mrs. John A. McCone; redesignated USS Pasig (AW–3) on 28 August 1944; acquired by the Navy from the Maritime Commission on 21 October 1944; and commissioned on 11 December 1944.

Following shakedown off California, Pasig sailed on 3 March 1945 to begin her mission of distilling and supplying fresh water to units of the Allied navies in the western Pacific.

Decommissioned in February 1947, she was berthed at San Diego, California until war again broke out in the Far East.

Final Disposition, sold for scrapping, 16 October 1975, to Levin Metals Corp. Pasig received 6 battle stars for her service during the Korean War.