Victor Sproule, 32, attacked Jim Edwards after he abandoned a game in south Belfast.
Another player was barred from playing for five years for racial abuse directed at Mr Edwards, a Scot.
Violence erupted as the match between two Boys’ Brigade veterans’ teams at Boucher Road playing fields was brought to a halt.
Donald Fry, secretary of the Old Boys’ League, said the referee was assaulted when he headed off the pitch to collect his gear.
“He went to the office to get the key for the referee’s room from the lady attendant,” Mr Fry said.
“When he turned to come out of the office, the player had stood in front of the doorway, put a hand on either side of it, and headbutted the referee, knocking him straight across the room.”
Sproule, from Sandy Row in Belfast, was playing for 38th Old Boys A Team, which has links to a Methodist church in the city. Their opponents, 8th Old Boys, have associations with the nearby Cook Centenary Presbyterian church.
The ban was handed down by the Co Antrim Football Association.
Northern Ireland Referees’ Association secretary Basil Marshall praised the tough punishment handed down. “It’s setting an excellent example that senior football should now follow. When they overstep the mark, they should be punished hard,” he said.
“There’s young kids at these games who see referees being pushed and the player gets away with a six-game ban. It isn’t setting an example.
“We are right behind this and congratulate the Antrim FA for doing it.”