| Tustumena Lake | |
|---|---|
| Dusdu Bena (Tanaina) | |
 The lower end of the lake seen from the Kasilof River outflow | |
  Tustumena Lake  Tustumena Lake | |
| Location | Kenai Peninsula, Alaska |
| Coordinates | 60°13′46″N 150°56′28″W / 60.22944°N 150.94111°W |
| Primary inflows | Glacier Creek, other small streams |
| Primary outflows | Kasilof River |
| Basin countries | United States |
| Max. length | 25 miles (40 km) |
| Max. width | 6 miles (9.7 km) |
| Surface area | 73,000 acres (30,000 ha) |
| Average depth | 80 feet (24 m) |
| Max. depth | 950 feet (290 m) |
| Shore length1 | 71 miles (114 km) |
| Surface elevation | 112 feet (34 m) |
| Islands | Caribou Island |
| 1 Shore length is not a well-defined measure. | |
Tustumena Lake (Dena'ina: Dusdu Bena) is a lake on the west side of the Kenai Peninsula in southcentral Alaska, within Kenai National Wildlife Refuge and near the town of Kasilof. Access is only via the Kasilof River, as there are no roads that lead directly to the lake.