USS L-3 (SS-42) was an L-class submarine of the United States Navy. Her keel was laid down on 18 April 1914 by the Fore River Shipbuilding Company in Quincy, Massachusetts. She was launched on 15 March 1915 sponsored by Mrs. Lew Morton Atkins, and commissioned on 22 April 1916 with Lieutenant (junior grade) D. J. Friedell in command.