The 1966-67 NHL season was the 50th season of the National Hockey League. Six teams each played 70 games. Since the 1942-43 season, there had only been six teams in the NHL, but this was to be the last season of the Original Six as six more teams were added for the 1967-68 season. This season saw the debut of one of the greatest defenceman in the game's history, Bobby Orr of the Boston Bruins.