| Isfayramsay | |
| Name Other: | Isfayramsoy |
| Pushpin Map: | Uzbekistan#Kyrgyzstan |
| Source1: | Alay Range |
| Mouth: | Great Fergana Canal |
| Mouth Coordinates: | 40.5902°N 71.8274°W |
| Progression: | Great Fergana Canal→ |
| Subdivision Type1: | Country |
| Subdivision Name1: | Kyrgyzstan, Uzbekistan |
| Discharge1 Location: | Üch-Korgon |
The Isfayramsay (Kirghiz; Kyrgyz: Исфайрамсай|Isfayramsay,[1] Uzbek: {{lang|uz-Latn|Isfayramsoy[2]) is a river in Kyrgyzstan and Uzbekistan. Its source is in the Alay Range, where it is fed by many glaciers.[1] Due to use for irrigation, it does not reach the Syr Darya anymore, but ends at the Great Fergana Canal north of Fergana. The river is long, and the watershed covers .[2] The main settlements along the river Isfayramsay are the city Quvasoy in Uzbekistan, and the villages Üch-Korgon and Maydan in Kyrgyzstan. Its largest tributaries are the Kichik-Alay, Sürmötash, Shibe and Tegermach. Its annual average flow rate is at Üch-Korgon.[2]