USS Admiral W. S. Benson (AP-120) began as an unnamed transport, AP-120, that was laid down on 10 December 1942 at Alameda, California by the Bethlehem-Alameda Shipbuilding Corp., under a Maritime Commission contract (MC hull 678). She was named Admiral W. S. Benson (AP-120) on 20 October 1943 and launched on 22 November 1943; sponsored by Miss Dorothy Lucille Benson, granddaughter of the late Admiral William S. Benson. She was accepted from the Maritime Commission on 23 August 1944 and commissioned the same day, Capt. Francis H. Gardner in command.