Jehu Baker (November 4, 1822 – March 1, 1903) was a U.S. Representative from Illinois. Born near Lexington, Kentucky, Baker moved with his father to Lebanon, Illinois, in 1829. He attended the common schools and McKendree University. He studied law and was admitted to the bar in 1846, entering private practice in Belleville, Illinois. He served as master in chancery of St. Clair County, Illinois from 1861-1865.