The Tegernsee (German pronunciation: [ˈteːɡɐnˌzeː] ⓘ) is a Zungenbecken lake in the Bavarian Alps in southern Germany.

The lake is the centre of a popular recreation area 50 kilometres (31 mi) south-east of Munich.

Resorts on the lake include the eponymous Tegernsee, as well as Bad Wiessee, Kreuth, Gmund, and Rottach-Egern.

The area around the lake is linked to Munich by rail through trains of the Bayerische Oberlandbahn, which, in the final part of their journey, travel over the tracks of the privately owned Tegernsee-Bahn.

Adolf Hitler owned a house on the shores of Tegernsee and reclused here following the suicide of his niece and girlfriend, Geli Raubal, in 1931.