A new norditerpenoid alkaloid has been isolated from the roots of Delphinium cuneatum. On the basis of 1H, 13C NMR, IR, and mass spectra, the structure of the alkaloid was established as 1alpha;,6β,14α-trimethoxy-7,8-dihydroxy-18-(2″-methyl) succinylanthranoyloxyaconane (16-demethoxymethyllycaconitirie). The roots of Delphinium cuneatum also contain the known alkaloid methyllycaconitine and N,N′-di(methoxycarbonyl)-3,4-diaminotoluene.