She was launched on 3 April 1939 sponsored by Miss Louise Shaw Hepburn, and commissioned on 22 July 1939 with Lieutenant (later Rear Admiral) Chester C. Smith in command.

Following shakedown and post-shakedown repairs at Mare Island, Swordfish operated out of San Diego, California, until early 1941, when she set sail for Pearl Harbor.

Hit amidships by one of three torpedoes, the cargo ship Atsutasan Maru erupted in a cloud of smoke and flames and disappeared beneath the waves.

Swordfish then returned to Manila Bay and embarked the High Commissioner of the Philippines, arriving Fremantle, Western Australia, on 9 March.

Swordfish got underway from Fremantle on 1 April for her third war patrol, with her primary mission being to deliver 40 tons of provisions to the besieged island of Corregidor.

During her sixth patrol, she possibly was involved in an accidental "friendly fire" attack in Misima Island harbor on HMAS Fauro Chief, which was damaged on 12 November 1942.

[10] She was involved in another friendly fire incident at 02:30 on 26 November 1942, when a United States Army Air Forces North American B-25 Mitchell bomber mistook Swordfish for a Japanese submarine and attacked her while she was on the surface off Cape Ward Hunt, New Guinea.

She again was the target of a friendly fire incident when at 09:25 on 7 February 1943 what her crew identified as a U.S. Army Air Forces B-17 Flying Fortress bomber mistakenly attacked her while she was on the surface 240 nautical miles (444 km; 276 mi) north-northeast of Kavieng, New Ireland, at 00°12′N 152°00′E / 0.200°N 152.000°E / 0.200; 152.000.

On 22 August 1943, she sighted her first target of the patrol, and quickly sent the 3,016-ton cargo ship Nishiyama Maru to the bottom, the victim of two torpedo hits.

[14] The depth charging caused her to lose power in her electrical systems, and when she dived at dawn the next day, she suffered two separate fires and nearly went right to the bottom; her captain managed to bring her back up, where she wallowed on the surface, only to have a Japanese patrol boat close on her.

[14] At around 2200 on 14 January, Swordfish detected another ship, and made radar contact at 7 nmi (8.1 mi; 13 km) on the Japanese navy's first genuine Q-ship,[14] the 2182-ton merchantman Delhi Maru, on her maiden voyage.

[14] She had been outfitted with sonar (which Swordfish had heard pinging), new watertight bulkheads, depth charge throwers, and concealed guns, specially to destroy submarines.

[16] In the dark, it was impossible to see the carrier, but radar made contact on the force at 16,000 yards (15,000 m) (8 nmi (9.2 mi)), making 27 kn (31 mph; 50 km/h).

On 9 June, the submarine found Japanese destroyer Matsukaze clearly illuminated against the horizon and sank the enemy ship with two torpedoes from her bow tubes.

Four hours later Kete heard heavy depth charging from this area, and it was believed that this attack might have been the cause of Swordfish's loss.

It is considered about equally likely that Swordfish was sunk by depth charge attack before she reached Okinawa for her special mission or that she was lost to a mine at that place.

A memorial to Swordfish exists in St. Paul, Minnesota, near the Como Park Zoo and Conservatory, just off Churchill Street on a rise a short walk south of Hamm Falls.