Abstract: In China, some species of Bupleurum (family Umbelliferae) have been used as Chinese traditional medicine under the name “Chai-Hu” for the treatment of fevers and influenza.In the present paper, the authors report a study on the investigation and exploitation of new medicinal resources of “Chai-Hu” in Qinghai Province and Xizang (Tibet) Autonomous Region where no one has studied this hitherto.18 species, 7 varieties, I form of Bupleurum and a new species (Bupleurum qinghaiense) have been discovered.The taxonomy and preliminary phytochemical studies of the roots of three medicinal plants, B. qinghaiense, B. rnarginatum var.stenophyllum and B.smithii var.parvifolium.are reported in this paper.

Key words: Bupleurum qinghaiense, Bupleurum smithii var, parvifolium, Bupleurum marginatum var, stenophyllum, Bupleurum spp. in Qinghai and Xizang