Bullen is one of the 20 Districts of Ethiopia, or woredas, in the Benishangul-Gumuz Region of Ethiopia. It is named after its highest point, Mount Bullen. Part of the Metekel Zone, Bullen is bordered by Dangur in the north, Mandura in the northeast, Dibate in the east, the Abay River on the south (which separates it from the Kamashi Zone), and by Wenbera in the west. Its largest settlement is Bullen.