Abstract:The region of Yunnan Plateau is a very natural one in floristic nature. Its seed plants flora has about 5545 species in 1491 genera and 248 families. It is basically subtropical in nature, obvious in horizontal and vertical vicariance, as well as the wide connection in geographical rela-tionships‘but specially with the regions of Sino-himalayan subkingdom. It seems that the region may be the birthplace of many Sino-himalayan floristic elements. According to the degree of abundance in endemic species and some physiographical features, the region can be floristically divided into three subregions: subregion of Central Yunnan Plateau, subregion of middle reacher of Mekong river and Red river, as well as subregion of SE Yunnan. These subregions have evi-dent differences in many aspects, the reason of that may be due to different geological back-grounds.