The 1990 2. divisjon was a Norwegian second-tier football league season.
From the 1991 season and onwards, the name of the second level of the Norwegian football league system has been 1. divisjon.
The bottom three teams inn both groups were relegated to the new 2. divisjon.
The second-placed teams, Bryne and Eik met Lillestrøm in the promotion play-offs.
Lillestrøm won the qualification round and remained in the Tippeligaen.