Abstract: Three alkaloids have been isolated from the roots of the Chinese drug Aconitum hemsleyanum Pritz collected from Emei Shah, Sichuan Sheng in China, and are provisionally named guayewuanine A, guayewuanine B and guayewuanine C. One of them was identified as yuanaconitine (guayewuanine B) by comparing their physical and chemical properties with authentic sample. Guayewuanine A was found to be a new compound having the molecular C31H43NO9, mp 120 ℃, by means of interpretation of its IR, MS and NMR spectra, its structure may be suggested as shown figure I.