Thornton Steve Stonebreaker (October 28, 1938 – March 28, 1995) was a professional American football linebacker in the National Football League. He played eight seasons for the Minnesota Vikings (1962–1963), the Baltimore Colts (1964–1966), and the New Orleans Saints (1967–1968). Son Mike also played in the NFL.
Stonebreaker committed suicide on March 28, 1995 by subjecting himself to carbon monoxide poisoning from a car exhaust.