Nautilus was a 66-foot (20 m) motor pleasure boat built at City Island, New York. She was commissioned into the United States Navy in 1917 as the motor patrol boat USS Nautilus (SP-559) (the fourth vessel to bear that name) and assigned to patrol and escort duties of the New York City area for the remainder of World War I.

See USS Nautilus and ships named Nautilus for other ships of this name.