| Club: | Panathinaikos |
| Season: | 1990–91 |
| Manager: | Vasilios Daniil |
| Chairman: | Yiorgos Vardinogiannis |
| League: | Alpha Ethniki |
| League Result: | Winners |
| Cup1: | Greek Cup |
| Cup1 Result: | Winners |
| Cup2: | European Cup |
| Cup2 Result: | Round of 32 |
| Pattern B1: | _vneck |
| Leftarm1: | 00AE73 |
| Body1: | 00AE73 |
| Rightarm1: | 00AE73 |
| Shorts1: | 00AE73 |
| Socks1: | 00AE73 |
| Leftarm2: | fff |
| Body2: | fff |
| Rightarm2: | fff |
| Shorts2: | fff |
| Socks2: | fff |
| Prevseason: | 1989–90 |
| Nextseason: | 1991–92 |
In the 1990–91 season Panathinaikos played for 32nd consecutive time in Greece's top division, the Alpha Ethniki. They also competed in the European Cup and the Greek Cup.
See main article: 1990–91 Alpha Ethniki.
See main article: 1990–91 Greek Football Cup.
See main article: 1990–91 European Cup.