The southern part of the Qinghai-Xixang (Tibet) Plateau and its adjacent.area sare rich in flora. There are 51 families, 101 genera and 220 species. The geographical compo-sitions of the flora in this region are very complex,they consist of the following geo-graphical elements; tropic-subtropic elements approximating to 8.33% of the entire flora in the region, tropic-temperate elements 22.71% , temperate elements 43. 18%, Cos-mopolitan elements 9.85% ,Qinghai-Xizang endemic elements 14. 39%,north polemoun-tain elements 1.51%. Temperate elements in this region are dominant. The dominant species of mires,Carex lasiocarpa,in this region is also found in northeast China,Finland and northern Amarica. The origin of mires of this region was earlier than northeast China and Finland .This shows that the southern part of the Qinghai-Xizang Plateau and adjacent areas may be the centre of origin and distribution of temperate elements