The 1989–90 Primera División season was the second category of the Spanish basketball league system during the 1989–90 season. It was the second played with the name of Primera División.
16 teams played this season.
A total of 16 teams contested the league, including 10 sides from the 1988–89 season, one relegated from the 1988–89 ACB, three promoted from the Segunda División and two Wild Cards.
| Team | Home city | |
|---|---|---|
| Atlético de Madrid | Madrid | |
| BC Andorra |  Andorra la Vella | |
| CAB Obradoiro | Santiago de Compostela | |
| Cajahuelva | Huelva | |
| Caja Badajoz | Badajoz | |
| CB Argaray | Pamplona | |
| CB Askatuak | San Sebastián | |
| CB Guadalajara | Guadalajara | |
| CB Las Rozas | Las Rozas | |
| CD Cajamadrid | Alcalá de Henares | |
| Choleck Llíria | Llíria | |
| Cirsa Hospitalet | Hospitalet de Llobregat | |
| Elosúa León | León | |
| Lagisa Gijón | Gijón | |
| Júver Murcia | Murcia | |
| Syrius Patronato | Palma de Mallorca |
Semifinal winners are promoted to Liga ACB.
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