Background: The purpose of this study was to determine whether there is any advantage for a continuous background infusion during patient controlled epidural analgesia(PCEA) for postoperative pain control. Methods: 60 patients scheduled for elective cesarean section under epidural anesthesia were assigned randomly in a double-blind fashion to receive fentanyl and bupivacaine by PCEA with or without background infusion for 48 hours postoperatively. Results: Total amount of fentanyl and bupivacaine consumption and degree of sedation were not significantly different between the two groups. Visual analogue scale(VAS) pain scores at 24, 36, and 48h and sleep disturbance were significantly lower in background infusion group. Conclusion: Administration of fentanyl with bupivacaine by continuous background infusion is appropriate for PCEA for postcesarean section pain control.