The film is based on the book "Goon: The True Story of an Unlikely Journey into Minor League Hockey" by Adam Frattasio and Douglas Smith. Footage from Smith's career as a hockey enforcer is shown during the films credits.
Seann William Scott gained weight for the role of Doug Glatt, as well as taking intensive skating lessons and fighting on ice.
Curt Keilback, who plays the role of Halifax's play-by-play announcer, is actually a former National Hockey League play-by-play announcer.
A great majority of the cast is comprised by Canadian actors, including the well-established actors in Hollywood like Jay Baruchel, Kim Coates, Alison Pill and Eugene Levy. The only non-Canadians in major roles are Minnesota-native Seann William Scott and New Yorker Liev Schreiber. Ironically, Baruchel plays an American character (a thickly-accented Massachusetts native) in the film, while Schreiber plays a Canadian character.
Jay Baruchel wanted to adapt the book into a film after noticing a lack of hockey comedies in recent years.
Georges Laraque: The former NHL enforcer has a small role as an enforcer for the Albany Patriots. His character fights both Glatt and Rhea during the movie.