| Lac de Lessy | |
| Location: | Haute-Savoie |
| Coords: | 45.9878°N 6.4381°W |
| Pushpin Map: | France Savoie |
| Basin Countries: | France |
| Area: | 7.1ha |
| Max-Depth: | 1.7m (05.6feet) |
| Residence Time: | 600 days |
| Elevation: | 1730m (5,680feet) |
Lac de Lessy is a lake at Le Petit-Bornand-les-Glières in the Haute-Savoie, France.