| Sumka | |
| Source1 Location: | Gremyachy Klyuch, Zelenodolsky District |
| Source1 Coordinates: | 55.9817°N 48.9711°W |
| Mouth: | Volga |
| Mouth Location: | Kuybyshev Reservoir near Vasilyevo, Zelenodolsky District |
| Mouth Coordinates: | 55.8293°N 48.6464°W |
| Subdivision Type1: | Country |
| Subdivision Name1: | Tatarstan, Russia |
| Length: | 37km (23miles) |
| Mouth Elevation: | 53m (174feet) |
| Basin Size: | 250km2 |
The Sumka (ru|Сумка; tt-Cyrl|Сумка) is a river in Zelenodolsky District of the Republic of Tatarstan, Russia, a left-bank tributary of the Volga. It is 37km (23miles) long, and its drainage basin covers 250km2. It begins near Gremyachy Klyuch and flows to the Kuybyshev Reservoir, Volga, forming the western border of Vasilyevo, Tatarstan.
The river valley comes through the Raifa section of the Volga-Kama Reserve. There the Sumka passes several major lakes, the biggest being Raifa lake. The maximal mineralization 200 mg/L. The maximal water discharge is 30m3/s. The river used to dry up in summer.