USS Niphon was a steam operated vessel acquired by the Union Navy during the American Civil War. She was used by the Navy to patrol navigable waterways of the Confederacy to prevent the South from trading with other countries. Niphon, a wooden and iron screw steamer launched at Boston, Massachusetts, in February 1863, delivered to the Navy at Boston on 22 April 1863; and commissioned at Boston Navy Yard on 24 April 1863, Acting Ensign Joseph B. Breck in command; and was formally purchased 9 May 1863.