Lake Zurich (Swiss German/Alemannic: Zürisee; German: Zürichsee) is a lake in Switzerland, extending southeast of the city of Zurich. It is also known as Lake Zürich and Lake of Zürich. It lies approximately at co-ordinates 47°15′N 8°41′E / 47.25°N 8.683°E / 47.25; 8.683.

Zürichsee is strictly the name of the part of the lake downstream of the dam at Rapperswil, mostly located within the canton of Zurich. The part upstream of the Rapperswil dam is called Obersee, and is shared between the cantons of St. Gallen and Schwyz.