Literature on ice hockey does not provide valuable comparisons for penalties assessed in different leagues during the same period of time. The purpose of this study is to describe and compare the nature and frequency of penalties occurring in minor, junior, university, and professional leagues. The procedure used in the analysis permits discrimination between “aggression” penalties that could intimidate the opponent and “tactical” penalties that tend to impede the opponent's skill. Excluding the minor hockey league, a statistical analysis showed fewer penalties in the National Hockey League (NHL) than in junior leagues. Further more, we can presume that differences between the leagues in the frequency of “major aggression” penalties (5 min) can be explained in part by variations in leagues' regulations. An example could be the full mask rule for minor, university, and one season of Quebec Major Junior Hockey League (1989/1990). Another reason could be the sanctions imposed after a “major aggression” penalty.