Propofol(Diprivan, England ICI) is a new intravenous anesthetic agent chemically unrelated to barbiturates or other intravenous anesthetic agents. It was found to produce rapid onset of anesthesia and early recovery similar to that Obtained with pentothal sodium. The purpose of the present study is to compare the cardiovascular and respiratory effect of propofol with the cardiovaseular and respiratery effeet of pentothal sodium. Sixty patients of ASA class l or 2 scheduled to undergo gynecological, orthopedic and abdominal procedures were classified randomly into 3 Groups. Group A were injected with pentothal sodium 5.0 mg/kg and Group B, C received propofol 2.0 mg/kg, 2.5 mg/kg respectively. The results were as follows, 1) Change of the systolic arterial pressure. Propofol 2.5 mg/kg produced the greatest decrease in systolic blood pressure when compared with other groups. 2) Change of the heart rate. Change of the heart rate was minimal after both doses of prepofol when compared with pentothal sodium. 3) Respiratory effect. Respiratory measurement in 20 unpremedicated surgical patients who received an induction dose of propofol 2.5 mg/kg showed significant respiratory depression. 4) Side effect. Excitatory effects and pain on injection were more frequent in propofol group than pentothal sodium group. Nausea, vomiting were more frequent in pentothal sodium group than propofol group.