Lyngby Lake (Danish: Lyngby Sø) is a lake located on the border between Lyngby-Taarbæk and Gladsaxe municipalities in the northern suburbs of Copenhagen, Denmark. It is the smallest of the four lakes that are located on Mølleåen. At the east end of the lake is an embankment with a lake promenade, S-train line and Lyngby bypass. A small portion of the lake, known as Lille Lyngby Sø is located on the east side of the embankment. Lyngby Lake has an area of 57.1 hectares. It is fed with water from Furesø through a short canal from the west and is drained at its eastern end.