Her keel was laid down as William B. Bankhead on 5 October 1943 by Delta Shipbuilding Company, in New Orleans, Louisiana, under a Maritime Commission contract (T. Z-ET1-S-C3).

Originally designed to carry dry cargo, Leopard was converted to a tanker, and departed Key West, Florida, on 18 January 1944 for the southwest Pacific.

For the rest of the war, Leopard continued harbor fueling duties in the vicinity of New Guinea.

Following V-J Day, the tanker departed Seeadler Harbor on 30 August 1945 and arrived Manila Bay on 9 September where she performed similar services.

Leopard remained in the Philippines until she sailed for the United States on 19 March 1946 arriving Norfolk, Virginia, on 11 May.