Abstract: The methyl-eugenol is an active principle isolated from the essential oil of Asarum forbesii Maxium. Pharmacological studies showed that methyl-eugenol had marked depressant effect on central nervous system.It was found to potentiate the hypnotic action of pentobarbital and thiopental and the central depressant effect of chlorpromazine. When injected intravenously, methyleugenol showed narcotic effect in rabbits, cats, dogs and monkeys. It caused disappearence of righting-reflex, pain sensation and hearing reflex and slowness of corneal reflex. Average narcotic time with methyl-eugenol varied with different species; rabbits (50mg/kg)13.9, cats (50mg/kg) 9.0; dogs (40mg/kg) 25.0, and monkeys (80mg/kg) 30/0 minutes. It also exhibited marked inhibition of the spontaneous E E G of the cortex and mid-brain RF.Methyl-eugenol exhibited slight depressant action on the cardiovascular system and decrease of blood pressureby 20～30 mmHg in cats and lowering of body temperature in rats.Rapid administration of the drug or overdosage brought about depressant action on respiration (decreased in frequency or even stopp) but it may quickly recover.It may be concluded that methyl-eugenol possesses narcotic action which is similar to commonly used short-acting anaesthetics.