A new norditerpene alkaloid named 8-O-methylhypaconine (1) was isolated along with twelve known alkaloids from the underground parts of an unknown species of Aconitum plant culti vated in Korea. Among the known alkaloids, two dianthramide glucosides, N-(2'-beta-glucopyra nosyl-5'-hydroxysalicyl)-5-hydroxyanthranilic acid methyl ester (2) and N-(2'-beta-glucopyranosyl-5'-hydroxysalicyl)-5-hydroxy-6-methoxyanthranilic acid methyl ester (3), were isolated from Aconitum plants for the first time. The structures were established on the basis of chemical and spectroscopic methods.