USS Guardfish (SS-217), a Gato-class submarine, was the first ship of the United States Navy to be named for the guardfish.

Guardfish was laid down by the Electric Boat Company at Groton, Connecticut. She was launched there on 20 January 1942, sponsored by Mrs. Edward J. Marquart, and commissioned at Naval Submarine Base New London New London, Connecticut, on 8 May 1942, Lieutenant Commander Thomas B. Klakring in command.

After conducting shakedown out of New London, Guardfish left that base on 28 June 1942 for Pearl Harbor via the Panama Canal, and arrived there on 25 July to prepare for her first cruise. Her first war patrol was in previously unpatrolled waters off northeast Honshū. Guardfish left Pearl Harbor on 6 August 1942, sank a trawler on 22 August, and two days later sank 3,114 ton cargo ship Seikai Maru off Kinkasan Harbor. Evading escort vessels, she proceeded up the coast and found a convoy on 2 September. Guardfish attacked the next day, sinking 5,253 ton Kaimei Maru and 1,118 ton cargo ship Tenyu Maru. Chita Maru, a 2,376 ton freighter, retreated into the harbor and anchored, but a long-range shot from Guardfish left her beached in the mud. Guardfish returned from her successful first patrol to Midway for refit on 15 September 1942.

Guardfish left Midway on her second war patrol on 30 September and headed for the East China Sea. Surviving an attack by patrolling aircraft on 19 October, Guardfish closed a seven-ship convoy 21 October, sinking a 4,000-ton freighter and 6,362 ton Nichiho Maru north of Formosa as the convoy scattered. After evading pursuing aircraft and surface ships, Guardfish returned to Pearl Harbor on 28 November 1942. For her success on these first two patrols, Guardfish received a Presidential Unit Citation.

Moving her base of operations to the Truk area, Guardfish left Pearl Harbor on 2 January 1943 to patrol off the Japanese stronghold. She sank Japanese patrol Boat No.1 (the former destroyer Shimakaze) on 12 January west of Kavieng, and a 1,300 ton cargo ship the next day. Attacked by the destroyer Hakaze on 23 January, Guardfish sank her with a well-placed torpedo. Moving south toward Rabaul, she attacked a large convoy near Simpson Harbor, but was driven off by concentrated shore fire and escort attacks. Guardfish ended her third patrol by arriving at Brisbane, Australia on 15 February 1943.

Her fourth war patrol was conducted in the Bismarcks, Solomons, and New Guinea area, and Guardfish recorded no kills on this cruise, 9 March to 30 April 1943.

Leaving Brisbane for the same waters on 25 May 1943, Guardfish sank the transport and hell ship, Suzuya Maru, and damaged another before being forced to dive by aircraft on 13 June. She picked up a surveying party on the west coast of Bougainville on 14 July and returned to Brisbane for refit on 2 August 1943.

Guardfish left Brisbane for her sixth war patrol on 24 August 1943, landing a reconnoitering party on Bougainville and then moving into cruising waters. She sank the 5,460 ton Kasha Maru on 8 October and subsequently spent two days as lifeguard ship during the air strikes on Rabaul. Guardfish embarked another reconnoitering party on 19 October at Tulagi, landed them on Bougainville, and took vital soundings in Empress Augusta Bay before re-embarking the Marine party on 28 October. These important missions were carried out two days before the American landings at Bougainville. Guardfish reached Brisbane, completing her sixth patrol on 3 November 1943.