Abstract:There are 9 genera 24 species and 3 varieties of Loranthaceae discovered in Xishuangbanna region of Yunnan Province,whitch make up 81.8% of the total 11 genera 45% of the total 60 species of China and 90% of the total 10 genera 60% of the total 45 species of Yunnan.The host of these parasic plant species and their populations of the host are changeable in aeeordance with the species of parasites.