| Turkish Cup | |
| Year: | 1990–91 |
| Other Titles: | Türkiye Kupası |
| Country: | Turkey |
| Num Teams: | 105 |
| Winners: | Galatasaray |
| Second: | Ankaragücü |
| Matches: | 104 |
| Goals: | 338 |
| Scoring Leader: | Hasan Yıldırım (5 goals) [1] |
| Prev Season: | 1989–90 |
| Next Season: | 1991–92 |
The 1990–91 Turkish Cup was the 29h edition of the tournament that determined the association football Süper Lig Turkish Cup (tr|Türkiye Kupası)[2] champion under the auspices of the Turkish Football Federation (tr|Türkiye Futbol Federasyonu; TFF). champion under the auspices of the Turkish Football Federation (tr|Türkiye Futbol Federasyonu; TFF). Trabzonspor successfully contested Bursaspor on both legs of the finals. The results of the tournament also determined which clubs would be promoted or relegated.
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