The Bös Fulen is a mountain in the Schwyz Alps, located on the border between the cantons of Schwyz (SZ) and Glarus (GL), Switzerland. It overlooks the valleys of Muotathal (SZ) and Linthal (GL). Politically, it is split between the municipalities of Muotathal and Glarus. Braunwald (GL) is the nearest locality.
With 2,802 metres (9,193 ft) above sea level, the Bös Fulen is the highest summit of the canton of Schwyz.