Mníšek consists of two municipal parts (in brackets population according to the 2021 census):[2] The German name Einsiedel was derived from Einsiedler, i.e. 'hermit'.

The highest point is the mountain Olivetská hora at 886 m (2,907 ft) above sea level.

The built-up area is situated in the valley of the Jeřice River and the Fojtka Stream.

[3] The I/13 road (the section from Liberec to the Czech-Polish border in Habartice) passes through the municipality.

Mníšek is located on two railway lines of local importance, heading from Liberec to Černousy and to Nové Město pod Smrkem.