| Tarjanne | |
| Pushpin Map: | Finland |
| Location: | Ruovesi, Virrat, Mänttä-Vilppula |
| Coords: | 62.1167°N 29°W |
| Catchment: | Kokemäenjoki |
| Basin Countries: | Finland |
| Area: | 54.872km2 |
| Depth: | 12.66m (41.54feet) |
| Max-Depth: | 67.78m (222.38feet) |
| Volume: | 0.695km3 |
| Shore: | 243.18km (151.11miles) |
| Elevation: | 96.1m (315.3feet) |
| Frozen: | December–April |
| Islands: | Siperia, Monosen Kuusinen, Palosaari, Vannottu, Kauttakala |
Tarjanne (also Tarjannevesi) is a medium-sized lake in Finland. It is situated in the municipalities of Ruovesi, Virrat and Mänttä-Vilppula in the Pirkanmaa region in western Finland. The lake is part of the Kokemäenjoki basin. The main inflows are the lake Vaskivesi and a chain of lakes north of it in the west and a chain of lakes from the lake Pihlajavesi in the north. The lake drains into the Lake Ruovesi in the south.[1]