Abstract:From the roots of Aconitum geniculatum Fletcher, seven diterpenoidalkaloids were isolated, six of which were identified as yunaconitine (1), crassicaulineⅠ(2), vilmorrianine C(3), talatisamine (4), chasmanine (5), and 8-deacetyl-yunaconitu-ne(6), geniconitine, a new diterpenoid alkaloid, was established as (7)by means of MS,IR, 1HNMR, 13CNMR, and chemical methods.