| Lake Sidihoni | |
| Other Name: | Danau Sidihoni (Indonesian) Tao Sidihoni (Batak) |
| Pushpin Map: | Indonesia Sumatra North |
| Location: | Samosir Island, Lake Toba, North Sumatra |
| Coords: | 2.6015°N 98.7448°W |
| Basin Countries: | Indonesia |
| Elevation: | 1295m (4,249feet) |
Lake Sidihoni is a lake located within Samosir Island which itself is an island within Lake Toba, in North Sumatra, Indonesia and is therefore notable for being a "lake on an island in a lake on an island". It is approximately 11–12 km to the east of hot spring pools at Pangururan.[1]