Abstract: OING YANG SHEN (Cynanchum otophyllum Schneid, Asclepiadaceae) is a plant widely distributed in southwest China. In Yunnan, its root is used as nourishing and roborant drug and in the treatment of convulsions of the child. The result of pharmacological study showed that the root of OING YANG SHEN has anticonvulsant action and therapeutic activity for chronic hepatitis.Two aglycones and one sugar were obtained from the hydrolysate of the crude glycoside by sillica column chromatography. On the basis of spectra, analysis (UV. IR. MS. ¹HNMR. and ¹³CNMR.), preparation of derivatives and chemical reactions, two of them were i dentifed as caudatin (Ⅰ) and digitoxose (Ⅲ). The third component was a new compound, its structure was established as C/D cis, △⁵, 3β, 8β, 14β, 17β- tetrahydroxy-12-O- p-hydroxybenzoylpregnan- 20-one, and named qingyangshengenin (Ⅱ).