The Boosmansbos Wilderness Area of 142 km2 (55 sq mi) is situated 20 km (12 mi) north of Heidelberg in the eastern Langeberg mountain chain of the Western Cape Province, South Africa.

Boosmansbos, i.e. 'angry man's forest', is named after a resident hermit of the early 19th century who had been known to scare youngsters who visited his apiaries.

The elevation reaches 1,637 m (5,371 ft) at Grootberg peak, located at the centre of the wilderness area.

Among the special fynbos plants conserved are Erica and everlasting species as well as the rare Langeberg rambling aloe.

Important forest tree species occurring in the valleys are sickle-leaved yellowwood, stinkwood and red alder.