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.