Three new diterpenoid alkaloids named polyschistine A, B and C were isolated from the roots of Aconitum polyschistum Hand-Mazz collected in Sichuan province in China. The roots of aconitum plants are frequently used for treatment of rheumatism, neuralgia and fracture in China. In continuation of our work on the constituents of Chinese aconitum plants, we now wish to report here the structural elucidation of three new C19-diterpenoid alkaloids, polyschistine A, B and C. The structures of polyschistine A, B and C were determined on the basis of their ¹H and ¹³C NMR spectra.