In this study the action of pancuronium given directly into the lateral ventricle on the mean blood pressure, heart rate, respiratory frequency and skeletal muscular contractility of the rabbit were investigated. Pancuronium, which a dose of 10ug/kg and 30kg/kg were given into the lateral ventricle of rabbit. 1) Intraventricular injection of 10ug/kg of pancuronium increased pulse rate, respiratory frequency and muscle contraction and the differences were not statiscally significant. 2) Intraventricular injection of 30ug/kg of pancuronium produced a gradual increase of respiratory frequency which began at 5 minutes after drug injection and continued over a half hour. The difference between control and experimental value was statistically significant (p<0.005) while pulse rate and muscular contractility were increased but not significant. 3) Mean blood pressure was not changed after intraventricular injection of the pancuronium.