The most prestigious club championship in the world is the
Stanley Cup, champion of the National Hockey League. However
winners of the Stanley Cup are very rarely referred to as "World
Champions." Other ice hockey leagues including Elitserien (known in
English as the Swedish Elite League), SM-liga (Finnish league),
Nationalliga A (Swiss League), the Kontinental Hockey League
(Russia and satellite states) also designate a league champion, not
a world champion.
If your talking international competition, Ice Hockey has two
main tournaments: An annual World Championship and the Olympic
games (Every 4 years). The current world champion is the Czech
Republic and the current Olympic champion is Canada.