BACKGROUND: Laparoscopic cholecystectomy is of benefit to reduce postoperative pain but many patients suffer from considerable pain after the surgery. The aim of this study was to investigate whether the preoperative infiltration of bupivacaine at the trocar site reduced the intensity of the postoperative pain or not. METHODS: Sixty patients who underwent elective laparoscopic cholecystectomy were selected. In a randomozed study, patients were divided into three groups. General anesthesia was induced with pentothal and succinylcholine, and maintained with vecuronium and isoflurane. After induction, the preincisional group (n = 20) received 0.25% bupivaciane 20 ml infiltration before skin incision and the postoperative group (n = 20) was given 0.25% bupivacaine 20 ml after peritoneal closure. The control group (n = 20) did not receive bupivacaine at any time. The first time of demand for analgesics and the amount of analgesics given during postoperative 48 hours were checked and recorded. The degree of postoperative pain was assessed hourly by visual analogue scale (VAS) score until 9 hours and checked once more at 24 hours postoperatively. RESULTS: The first times of demand for analgesics were significantly delayed in the preoperative group (12.1+/-6.0 hours) as compared with the control (2.9+/-1.6 hours) and postoperative groups (6.2+/-3.9 hours). The demand for analgesics until 9-hour postoperation by the preincisional group (10.5+/-14.7) was significantly less than that of the control (42.0 20.4) and postoperative groups (31.5+/-22.8). The VAS score of the preoperative group was lower than that of the control or postoperative groups during the postoperative 24 hours. CONCLUSIONS: Local infiltration of 0.25% bupivacaine into the trocar site preincisionally could reduce the early postoperative pain after laparoscopic cholecystectomy.