1989–90 I-Divisioona season
| 1989–90 I-Divisioona season | |
|---|---|
| Season champions | Porin Ässät |
| Runners-up | Hockey-Reipas |
| Promoted to SM-liiga | Porin Ässät and Hockey-Reipas |
| Relegated to II-Divisioona | Hokki-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.