| Turkish Cup | |
| Year: | 1965–66 |
| Other Titles: | Türkiye Kupası |
| Country: | Turkey |
| Num Teams: | 67 |
| Defending Champions: | Galatasaray |
| Winners: | Galatasaray (4th title) |
| Second: | Beşiktaş |
| Matches: | 73 |
| Goals: | 209 |
| Scoring Leader: | Abdullah Çevrim Selim Soydan (4 goals each) |
| Prev Season: | 1964–65 |
| Next Season: | 1966–67 |
The 1965–66 Turkish Cup was the 4th edition of the annual tournament that determined the association football Süper Lig Turkish Cup (Turkish: Türkiye Kupası)[1] champion under the auspices of the Turkish Football Federation (Turkish: Türkiye Futbol Federasyonu; TFF). Galatasaray successfully contested Beşiktaş 1–0 in the final. The results of the tournament also determined which clubs would be promoted or relegated.
In the Quarter Finals round, Fenerbahçe, Galatasaray, Gençlerbirliği, and Beşiktaş advanced to the Semi-Finals round; Denizli Karagücü, Ankaragücü, Adana Demirspor, and Bursaspor were eliminated.
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In the Semi-Finals round, Galatasaray and Beşiktaş advanced to the final; Fenerbahçe and Gençlerbirliği were eliminated.
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