USS S-8 (SS-113) was a second-group (S-3 or "Government") S-class submarine of the United States Navy. Her keel was laid down on 9 November 1918 by the Portsmouth Navy Yard. She was launched on 21 April 1920 sponsored by Mrs. Roy W. Ryden, and commissioned on 1 October 1920 with Lieutenant Commander Eric F. Zemke in command. The two divisions — which comprised Submarine Flotilla 3 (SubFlot 3) — operated out of Cavite for the next three years, with annual visits to ports in China. They finally departed Cavite on 29 October 1924, and arrived at Mare Island, California on 30 December.