From 19 March to 4 July 1945 "Cowanesque" operated out of Ulithi refueling ships of the 5th Fleet at sea in support of the Iwo Jima and Okinawa operations. She reported to Okinawa on 8 July for convoy duty between that island and Ulithi until the end of the war, and continued to base on Okinawa as she supported the occupation. Among her duties was refueling ships sweeping mines in the Yellow Sea. On 28 October, she sailed for San Francisco, arriving on 15 November. "Cowanesque" was placed out of commission 30 January 1946 and transferred to the Maritime Commission.