The 1990Tippeligaen began on April 29, 1990, and ended on 7 October 1990.
Twenty-two games were played with 3 points given for each win and 1 for each draw. Number eleven and twelve were relegated. The winners of the two groups of the Second Division was promoted, as well as the winner of a series of play-off matches between the two second placed teams in the two groups of the Second Division and number ten in Tippeligaen.
This was the first year the top flight of Norwegian football would be called Tippeligaen, from its sponsor, Norsk Tipping. However, the league was still unofficially known by its former name 1. Divisjon in the general public. And by the end of the season, it was decided to let the second level of Norwegian football inherit the name 1. Divisjon from the 1991 season to strengthen Tippeligaen as a brand.
Sogndal and Lyn were promoted from the Second Division.
The qualification matches were contested between Lillestrøm (10th in Tippeligaen), Bryne (2nd in the Second Division - Group A), and Eik-Tønsberg (2nd in the Second Division - Group B). Lillestrøm won and stayed in Tippeligaen.