The 1990–91 Cypriot First Division was the 52nd season of the Cypriot top-level football league. Apollon Limassol won their 1st title.
Format
Fourteen teams participated in the 1990–91 Cypriot First Division. All teams played against each other twice, once at their home and once away. The team with the most points at the end of the season crowned champions. The last two teams were relegated to the 1991–92 Cypriot Second Division. The 12th-placed team faced the 3rd-placed team of the 1990–91 Cypriot Second Division, in a two-legged relegation play-off for one spot in the 1991–92 Cypriot First Division.