Background: The aim of this randomized controlled study was to compare the postoperative analgesic efficacy of intraperitoneal bupivacaine versus levobupivacaine in patients undergoing laparoscopic cholecystectomy. Methods: We randomly divided 90 patients undergoing elective laparoscopic cholecystectomy into 3 groups. A dose of 0.125% bupivacaine (Group B) 80 ml or 0.125% levobupivacaine (Group L) 80 ml or 0.09% NaCl (Group P) 80 ml was instilled intraperitoneally at the end of the procedure, before removal of the trocars. All patients had a standard anesthetic. Tramadol was administered intravenously via a patient controlled analgesia pump as a rescue analgesic in all patients. Postoperative pain scores were assessed at 30 minutes, 1, 2, 4, 6,12 and 24 hours after surgery by using a visual analog scale. The primary end point of this study was to compare tramadol consumption of the three groups at the postoperative 24 h. Total tramadol consumption, first analgesic requirement time and adverse effects were recorded. Results: Group B experienced significantly less pain (P <0.01) than the placebo group at 6 h, 12 h and 24 h postoperatively during rest. Group L registered significantly lower visual analog scale scores (p <0.01) than the placebo group at 12 h during rest. During movement, visual analog scale pain scores were lower in group B than Group P (P <0.01). Additionally, total tramadol consumption was significantly lower in Group B than the other groups. First analgesic requirement time was shorter in the placebo group compared with group B and group L (P <0.05). There was no significant difference between the groups with respect to right shoulder pain, total nausea and vomiting. Conclusion: Intraperitoneal instillation of bupivacaine 0.125% 80 ml (100 mg) is more effective than levobupivacaine 0.125% 80 ml (100 mg) in reducing the postoperative pain after laparoscopic cholecystectomy.