Propofol containing solvents such as soybean oil, egg phosphatide, glycerol, is known to arouse pain on intravenous injection in most patients. The study was undertaken to evaluate the efficacy of the two methods in preventing pain during injection of propofol on induction of anesthesia. Patients were allocated randomly into three groups. The one to receive unmodified propofol as control, the other to have injection of propofol with lidocaine added O.l mg/kg and another to have administration of propofol cooled in 0-4 degrees C. The results showed that propofol with lidocaine mixed and propofol cooled in 0-4 degrees C significantly lowered the incidence of pain during the intravenous injection of the drug and that addition of lidocaine and cooling had no untoward effect on the cardiovascular system.