Abstract: Salvia miltrorrhiza Bge (S. M. B.) is a medicinal herb widely used in traditional Chinese medicine. In this article some results of studies on the action of S. M. B. on the central nervous system is reported.Crude extract of S. M. B. was used in the experiments. The dosage was expressed in terms of the weight of the crude drug. All drugs were prepared in aqueous solution and administered by the intraperitoneal or oral route to groups of 10—20 animals.When S. M. B. was administered, animals became calm and tame. The spontaneous activity was significantly decreased and the effect increased with increased dosage. At the dosage of 0.5 g/kg, the spontaneous activity was only slightly diminished, while at 4 g/kg and 16 g/kg the percentages of inhibition were 60% and 90%, respectively. The inhibitory effect on spontaneous activity of chlorpromazine at the dosage of 0.5 mg/kg or of meprobamate at 100 mg/kg was not obvious, but when given in combination with S. M. B. the inhibitory effect was markedly enhanced. The S. M. B. did not show obvious anticonvulsive effect, but the stimulating effect of amphetamine on spontaneous activity was antagonized by S. M. B..While 2 of 20 control animals were put into sleep after administration of 25 mg/kg of pentobarbital, all of 20 animals fell into sleep after treatment by pentobarbital and S. M. B.. After the administration of 125 mg/kg of barbital, 1 in 10 animals fell into sleep. When the barbital was used in combination with S. M. B., 9 out of 10 animals fell asleep. Chloral hydrate given by mouth at 250 mg/kg was not hypnotic. However, when it was administered in combination with S. M. B., 4 out of 10 animals fell a sleep. Although S. M. B. can strengthen markedly the hypnotic effect of barbiturates as well as nonbarbiturate, sleep is not induced, however, by S. M. B. alone. It may be postulated on the basis of these results that S. M. B. possesses the properties of a tranquilizer.