Suisun was laid down on 4 October 1942 by Lake Washington Shipyard at Houghton, Washington. She was launched on 14 March 1943, sponsored by Mrs. C. W. Martyr, and commissioned on 13 September 1944 with Commander James. J. Vaughan in command.

After fitting out, Suisun steamed to San Diego, California, on 18 October 1944 for her shakedown cruise, which lasted until 21 November 1944. She then had a post-shakedown yard availability period

World War II operations 1944-1945

Central Pacific operations

Suisun departed the United States West Coast for Hawaii on 7 December 1944. She arrived at Pearl Harbor, Hawaii, on 14 December 1944, and departed for Eniwetok in the Marshall Islands on 18 December 1944. She remained at Eniwetok from 26 December 1944 to 1 January 1945, when she sailed to the Marianas Islands. From there she went to Ulithi Atoll in Caroline Islands for three days.

On 13 January 1945, Suisun got underway for Kossol Passage in the Palau Islands, and operated there until 5 February 

Operations in the Ryukyu Islands

Suisun departed Saipan in the Marianas on 20 April 1945 and anchored at Kerama Retto in the Ryukyu Islands, on 25 April 1945. She tended seaplanes until forced to leave for Saipan to pick up emergency aviation supplies on 15 June. She returned to Kerama Retto on 26 June 1945 and resumed seaplane tending operations there through the cessation of hostilities withJapan on 15 August 1945, which brought World War II to a close.

Honors and awards

Suisun received two battle stars for her World War II service. 

Operations in Japan 1945

Suisun departed Kerama Retto for Japan on 16 August 1945. She entered Tokyo Bay on 28 August 1945, the eighth Allied ship to enter Tokyo Bay at the end of the war and was present for Japan's formal surrender ceremony there on 2 September 1945. She operated in Tokyo Bay until 16 November 1945, when she departed for Pearl Harbor. After calling at Pearl Harbor, she continued on to theUnited States.