1989–90 I-Divisioona season

1989–90 I-Divisioona season
Season championsPorin Ässät
  Runners-upHockey-Reipas
Promoted to SM-liigaPorin Ässät and Hockey-Reipas
Relegated to II-DivisioonaHokki-Salo and KooVee

The 1989–90 I-Divisioona season was the 16th season of the I-Divisioona, the second level of Finnish ice hockey. 12 teams participated in the league, and Ässät Pori won the championship. Ässät Pori and Hockey-Reipas Lahti qualified for the promotion/relegation round of the SM-liiga.