Zervreilasee is a reservoir located south-west of Vals in the canton of Graubünden, Switzerland.
The lake has a surface area of 1.61 km² and an elevation of 1,862 m. The maximum depth is 140 m. The dam is 151 m high and was completed in 1957.
The Zervreilasee, located near the upper end of the Valser Tal, is surrounded by peaks of the Adula Alps, some rising to over 3,000 metres.
Other peaks are the Fanellhorn (3,124 m), the Frunthorn (3,030 m), Piz Scharboda (3,122 m), the Plattenberg (3,041 m) and the Furggeltihorn (3,043 m).
The Zervreilahorn is a sharp peak overlooking the lake from its south-west side.