The Sierra del Lacandón is a low karstic mountain range in Guatemala and Mexico.

It is situated in the north-west of the department of El Petén and the south-east of Chiapas.

[1] Its highest points are located near the Mexican border at coordinates 17°14′39″N 91°12′08″W / 17.244195°N 91.202145°W / 17.244195; -91.202145 and 17°11′42″N 91°05′10″W / 17.195087°N 91.086102°W / 17.195087; -91.086102 The range consists of southeast to northwest trending ridges of folded Cretaceous limestone and dolomite hills rising above the lowlands of the Petén Basin.

It is also considered of great importance for the Mesoamerican Biological Corridor as it connects the protected areas of northern Guatemala with those of southern Mexico, like the Montes Azules Biosphere Reserve in Chiapas.

Several ancient Maya archaeological sites are located within the park boundaries.