Peter G. Barnes (born August 31, 1945 in Keatchie, Louisiana) is a former American football linebacker who played professionally in the American Football League (AFL) and the National Football League (NFL). He played college football at Southern University. He played professionally in the AFL for the Houston Oilers in 1967 and 1968, and the San Diego Chargers in 1969. Then he played in the NFL for the Chargers (1970–1972), the St. Louis Cardinals (1973–1975), and the New England Patriots (1976–1977).