For the first time, using a MS 25RF chromato-mass spectrometer with a Carlo Erba 5160 chromatograph and a packed column, the possibility of the partial separation of the mixture of diterpene alkaloids of various types from the roots of Aconitum septentrionale has been shown. From their chromatographic parameters and mass-spectral characteristics 18 bases have been detected, including a new one with M+ 407 which was probably deoxydelcorine, while 6-O-methyldelcorine and 6-O-methyleldelidine have been found in plants for the first time. © 1990 Plenum Publishing Corporation.