Abstract: It was proved that palmatine inhibited the epinephrine effect when tested on the perfusion preparations of Laewen-Trendelenburg's toad hind leg, isolated rat seminal vesicle and on the blood pressure (acute method) of rabbits. dl-Tetrahydropalmatine in- hibited the effect of 5-HT when tested on the isolated preparations of the rat uteri, colon, and stomach in vitro, but dl-tetrahydropalmatine could not release 5-HT from the tissue. This was demonstrated by the method of determining the urine level of 5- hydroxyindole acetic acid (5-HIAA), which is the decomposed product of 5-HT in the animal body. Moreover, the ACTH-like action and the bacteriocide action of both alka- loids were also reported in this paper. The anticholinesterase effect of palmatine was also observed. Based on the comparative pharmacology, it may be held that most likely palmatine, dl-tetrahydropalmatine, and ergot alkaloids (among which lysergic acid diethylamide, LSD is the famous one) have the analogous pharmacological mechanism when reacted with the biochemical systems existing in the organism.