A report has been made previously [1] on the phenolic components of Atragene sibirica L. (Siberian clematis) family Ranunculaceae. In a study of its chemical composition, we detected alkaloids which, on the basis of the Lieberman-Burchard reactions with concentrated H2SO4, can be assigned to the steroid or diterpene series. We now give information obtained in their study. The bases accumulate in predominating amount (0.06%, gravimetric method [2]) in the hypogeal part, and therefore we investigated the roots of plants collected in the flowering phase in the Altai krai. We isolated five alkaloids (I-V) from the roots and identified compounds (I) and (IV) as the alkaloids delphinine and aconidine respectively from their physicochemical properties, IR spectra, and direct comparison with authentic samples.