Guardfish was a Gato-class submarine, SS-217. Electric Boat at Groton laid her down on 1 April 1941. Mrs. Edward J. Marquart sponsored her at the launch on 20 January 1942, and the Navy commissioned her at New London on 8 May 1942. Thomas Burton Klakring had her from that day.
Near Kavieng on 12 January 1943 she sank the destroyer Shimakaze of 1920, which had been renamed Patrol Boat No. 1 and was escorting the oiler Akebono. That is not the Shimakaze of 1942. The Dictionary of American Naval Fighting Ships calls the ship a Japanese patrol craft. On 23 January, while escorting the seaplane tender Akitsushima, the destroyer Hakaze attacked her. She sank Hakaze with a torpedo. Admiral Chester W. Nimitz later presented Klakring the Navy Cross for the early patrols. A Presidential Unit Citation covers her first two patrols. Norvell Gardiner Ward relieved Klakring on 18 May 1943.
On her seventh patrol she sank the oiler Kenyo Maru on 14 January 1944. On 1 February, off the southern entrance of Truk, she sank the destroyer Umikaze, which was escorting a convoy from Saipan. Umikaze sank slowly. Two hundred fifteen of her men got off, and fifty were lost. Guardfish then did lifeguard duty off Truk. She reached Pearl Harbor on 18 February and went on to San Francisco for repairs. Ward was relieved on 27 October 1944. He received the Navy Cross while he had her.
She was decommissioned on 25 May 1946. From 18 June 1948 she trained the Naval Reserve at New London. She was placed out of service on 1 June 1960. uboat.net records the strike as 1 October 1960. On 10 October 1961 she was sunk as a target off New England.