Otho Robards Singleton (October 14, 1814 – January 11, 1889) was a U.S. Representative from Mississippi and a member of the Confederate States Congress during the American Civil War. Born near Nicholasville, Kentucky, Singleton attended the common schools. He graduated from St. Joseph's College, Bardstown, Kentucky, and from the law department of the . He was admitted to the bar in 1838 and commenced practice in Canton, Mississippi. He served as member of the State house of representatives in 1846 and 1847. He served in the State senate 1848–1854.