Arthur James Cumnock (February 12, 1868 – June 8, 1930) was an American football player.
He and Amos Alonzo Stagg were selected as the ends on the first College Football All-America Team in 1889.
Cumnock invented the first nose guard.
He is also credited with developing the tradition of spring practice in football; in March 1889, Cumnock led the Harvard team in drills on Jarvis field, which is considered the first-ever spring football practice.