Arnensee (French: Lac d'Arnon) is a lake in canton of Bern, Switzerland.

The lake in the municipality of Gsteig is used as a reservoir by Romande Energie.

The dam was built in 1942.

Its volume is 10.5 mio m³ and surface area 0.456 km2.

This article related to a lake in the canton of Bern is a stub.