The Northern Senior A Hockey League was an Ontario Hockey Association Senior league in the 1980s and 1990s. Also known as the Northern Intermediate B League and Northern Senior B League in the 1980s, the league was promoted to Senior A when it absorbed the Central Senior B Hockey League. The leagues beginnings came with the 1970's OHA Intermediate C Hockey League.
The league was a competitor for the Hardy Cup in the late 1980s. Around 1992, the league merged with the Southern Senior A Hockey League to form the Southwestern Senior A League, now known as Major League Hockey.