| Competition: | 1.Lig |
| Season: | 1989–90 |
| Winners: | Beşiktaş 8th title |
| Relegated: | Malatyaspor Altay Samsunspor Adana Demirspor Sakaryaspor |
| Continentalcup1: | European Cup |
| Continentalcup1 Qualifiers: | Beşiktaş |
| Continentalcup2: | Cup Winners' Cup |
| Continentalcup2 Qualifiers: | Trabzonspor |
| Continentalcup3: | UEFA Cup |
| Continentalcup3 Qualifiers: | Fenerbahçe |
| League Topscorer: | Feyyaz Uçar (28 goals) |
| Matches: | 306 |
| Total Goals: | 819 |
| Prevseason: | 1988–89 |
| Nextseason: | 1990–91 |
Statistics of the Turkish First Football League in season 1989/1990.
It was contested by 18 teams, and Beşiktaş J.K. won the championship.