Basum (autonym: brag gsum 'three cliffs'; Basong 巴松话) is a Central Tibetan language spoken by about 2,500 people in Gongbo'gyamda County 工布江达县, Nyingtri Prefecture, Tibet, China. Basum is spoken by 13.5% of the population of Gongbo'gyamda County.Basum is spoken in Cuogao Township 错高乡 and Xueka Township 雪卡乡 of Gongbo'gyamda County 工布江达县, Nyingtri Prefecture, Tibet, China (Qu, et. al 1989).