Abstract: There is rich biodiversity and special geographical position in Baerluke Mountain in Xinjiang. In this paper,we analyzed the flora composition and geographical composition of Baerluke Mountain in detail,and briefly described the endemic and rare and endangered species in this flora. Results indicate: there are three biggest families in Baerluke Mountain,which are Asteraceae,Poaceae and Fabaceae,including 424 species,accounted for percent 32.6 of the total of the species in the mountain. In the distribution area type of families,the Cosmopolitan distribution area type is the biggest one,including 42 families,accounted for percent 28.9. In the distribution area type of genera,the North Temperate distribution area type is the dominant one,including 178 genera,accounted for percent 38.6. In the distribution area type of species,the temperate elements are dominant; among them the Old World Temperate distribution area type is the most widespread one,including 297 species. The second large component of this flora is Tethyan species,most of them are the mutual species for both Kazakhstan flora and Zhungaer flora,and this means study area is the confluence of Iran-Turan flora and Zhungaer flora. In addition,being the bridge between Siberian (Altai) and Tianshan flora from north to south,study area was the border for some species of these two big floras. There are over 50 species listed into the rare and endangered species in study area,and 6 species endemic to Baerluke Mountain. The study could provide basic data for the protection of wildlife in this area,environmental protection and nature reserve,the promotion national protected areas. It is of great practical significance to protect nature reserve,the original ecology,the rare and endangered flora composition in Baerluke Mountain.

Key words: vascular plants, flora, endemic species, Baerluke Mountain, Xinjang