Algorab was laid down as (AK-25) under a Maritime Commission contract (MC hull 20) on 10 August 1938 by the Sun Shipbuilding & Drydock Co., Chester, Pennsylvania; launched on 15 June 1939; sponsored by Miss Mary Aldrich; acquired by the Navy on 6 June 1941; and commissioned at Boston, Massachusetts, on 15 June 1941, Comdr. Thomas B. Inglis in command.