The USS S-33 was a United States Navy submarine, part of the S-class fleet, commissioned in 1919. Designed for coastal defense and reconnaissance, it was equipped with torpedoes and had a displacement of around 1,000 tons when submerged. The submarine was primarily used during the interwar period and World War II. Throughout its service, the USS S-33 conducted various training exercises and patrols. It was decommissioned in 1945 and later sold for scrap in 1946. The submarine is notable for being one of the early vessels in the evolution of modern submarine warfare.