Background: Postoperative pain is one of the most common complaints after elective laparoscopic cholecystectomy. The present study was aimed to evaluate the effect of paravertebral block using bupivacaine with/without fentanyl on postoperative pain and complications after laparoscopic cholecystectomy. Materials and Methods: This study was done on 90 patients scheduled to undergo elective laparoscopic cholecystectomy. Patients were assessed in two groups: The case group received bupivacaine and fentanyl, and the control group received bupivacaine and normal saline. Primary outcomes were severity of postoperative pain at rest and during coughing. Secondary outcomes were postoperative cumulative morphine consumption and the incidence of side-effects. Results: Pain score at rest before surgery, after recovery, hour-1 and hour-6 was not significantly different between the groups. But in hour-24 cases, the pain score during coughing was significantly higher than controls. Severity of pain at rest in time points was not different between groups. The frequencies (%) of moderate pain at mentioned times in case and control groups were 64, 31, 16, 9, 0 versus 67, 16, 7, 4, and 0, respectively. Pain score during coughing was lower in controls at hour-24 in comparison with cases, but in other time points was not significant. The control group significantly received more total dose of morphine in comparison with cases group. Nausea, vomiting and hypotension were similar in groups, but pruritus was significantly different between the groups. Conclusion: Adding fentanyl to bupivacaine in paravertebral block did not significantly improve the postoperative pain and complications after laparoscopic cholecystectomy. However, further studies are needed to be done.