Cecil Frank Isbell (July 11, 1915 – June 23, 1985) was an American football quarterback and coach. He played five years in the National Football League (NFL) with the Green Bay Packers, leading them to the NFL Championship in 1939. He retired after the 1942 season to become an assistant coach at his alma mater, Purdue University, and the following year became its head coach for three seasons.