Course treatment with diterpene alkaloids of Aconitum baicalense in mice reduced the time of immobilization in the tail suspension test and produced an antiexudative effect in mouse model of serotonin-induced edema. In the open field test, application of alkaloids did not change the total motor activity, orientation and exploratory behavior, and emotional reactions of animals. Experimental data suggest that diterpene alkaloids of Aconitum baicalensis exhibit antidepressant properties, possibly due to modulation of sensitivity to serotonin.