We report three cases in which the target-controlled propofol infusion technique was used in obese patients for general anesthesia. General anesthesia was induced by intravenous administration of fentanyl 150-300 micrograms and ketamine 50-80 mg and propofol 2 micrograms.ml-1 to achieve a target blood concentration by target-controlled infusion system. Anesthetic maintenance was achieved by ketamine 1 mg.kg-1.h-1 for 1 hour after the induction, propofol at target blood concentration of 2-3.5 micrograms.ml-1 and the intermittent epidural injection of 1.5% lidocaine through an epidural catheter. The surgical procedures were uneventful. The estimated blood concentrations of propofol at emergence from anesthesia calculated by ConGrace ranged from 1.49-1.69 micrograms.ml-1, and it took 230-300 seconds to emerge from anesthesia. The target-controlled propofol infusion technique appears useful to control the depth of anesthesia in obese patients.