John Regins "Monty" Monahan (November 15, 1908 – April 23, 1979), was an American professional football player in the National Football League (NFL).

He played college football for the Ohio State Buckeyes.

A native of Pittsburgh's Greenfield neighborhood, Monahan traveled to Ohio State where he played for the Buckeyes.

He was part of the 1935 Lions team that won the NFL championship.

Monahan played two additional games with the Chicago Cardinals during the 1939 NFL season.