Abstract: A comparative study on flora of the seed plants from the Daxigou region of the upper Urumqi River is carried out. There are about 406 species, 198 genera, 46 families of the seed plants in this region. About the constitutive of the families, the cosmopolitan distribution plays the most important role; about that of genera, the north temperate distribution is dominant; and about that of species, the temperate Asia distribution is the most. Analyzing the floristic elements o f the region, the Daxigou flora is a part of East Tianshan flora. It shows apparently the typical characteristics of Temperate Zone. It is a mountain flora and has vertical distribution. Most of the plants distribute in the middle of the mountain. Comparing the common genera and species of Daxigou flora with those in the adjacent regions, there is a close affinity between the Daxigou flora and Bei-Qilian shan flora. The flora of the region is very different from Xinjiang desert region, and there is a rather weak affinity between them. It seems likely to be a common flora origins among the three regions: Daxigou region, Bei-Qilianshan region and Neimongol grassland region.

Key words: the Urumqi river, Daxigou region, Floristic elements