Lago di Poschiavo is a natural lake in the Val di Poschiavo in the Swiss canton of the Grisons .

It lies at an elevation of 962 m (3,156 ft), a length of 2.5 km (1.6 mi), a surface area of 1.98 km2 (0.76 sq mi) and a maximum depth of 85 m (279 ft). The lake is both fed and drained by the Poschiavino river and drains to the south, with its water eventually reaching the Mediterranean via the rivers Adda and Po.

The lake lies within the municipality of Poschiavo, and the villages of Le Prese and Miralago lie at its northern and southern ends respectively. The Bernina railway line runs alongside the western side of the lake, with stations at Le Prese and Miralago. The main valley road (Hauptstrasse 29) follows a higher route on the same side of the lake.