| Lac du Malsaucy | |
| Location: | Territoire de Belfort, Bourgogne-Franche-Comté |
| Pushpin Map: | France Bourgogne-Franche-Comté |
| Basin Countries: | France |
| Length: | 1.5km (00.9miles) |
| Width: | 0.5km (00.3miles) |
| Area: | 64ha |
Lac de Malsaucy is a lake in the Territoire de Belfort, Franche-Comté, France. The lake with a surface of is 0.64 km2 shared by three communes: Evette-Salbert, Lachapelle-sous-Chaux and Sermamagny.
The rock festival Eurockéennes is held each July on an isthmus on the lake.