I-15 was an Imperial Japanese Navy B1 type submarine commissioned in 1940 that served during World War II. She supported the Japanese attack on Pearl Harbor, operated off the United States West Coast, and took part in Operation K-1, the Aleutian Islands campaign, and the Guadalcanal campaign, including the Battle of the Eastern Solomons and the Battle of the Santa Cruz Islands, before she was sunk in November 1942 during her fourth war patrol.