Abstract: The toxicity of "76017" extracted from the fibrous root of San Chi Panax rotoginseng (Burk) F. H. was found to be rather low. Its LD₅₀ in mice given intravenously was 836±17 mg/kg.Three to five minutes after intravenous injection of 76017 at the dosage of 25～50 mg/kg to open chest anesthetized cats the peak coronary flow was increased by 79% over the initial value. On the other hand, the blood pressure falled transiently, while the heart rate and oxygen comsumption decreased by 24.3% compared with the initial value.Experiments with Langendorff's rabbit heart showed that on the addition of 0.1～0.2 ml of 2% 76017 to the infusion system the peak coronary flow was increased by 17.5% and 48% respectively, the heart rate was slowed slightly and the contractile force enhanced by 48%.On adding 2% 76017 to the infusion system of isolated organ, the effluent flow from rabbit kidney, ear and hindlimb was found to be increased by 50%, 57% and 32% respectively at the small dosage of 0.1 ml and by 70%, 64% and 33% when the dosage was doubled.