To investigate whether preoperative oral gabapentin could reduce postoperative pain, analgesic consumption and the occurrence of catheter-related bladder discomfort (CRBD). Methods: In this study, participants randomly received either 600 mg gabapentin or placebo orally 2 h prior to transurethral prostate resection. Visual analogue scale and Ramsay sedation scale was utilized to assess pain intensity and sedation status after surgery. Intravenous 1.5 mg.kg-1 tramadol was used for postoperative analgesia. Pain intensity, sedation status, CRBD, tramadol consumption, side effects and the overall satisfaction degree were assessed and recorded for 48 h after tracheal extubation. Results: Ninety participants given gabapentin and 91 participants given placebo completed the study. Lower visual analogue scale scores, less tramadol consumption, longer time to the first analgesic requirement, lower incidence of CRBD and nausea and higher satisfaction degree were detected in the patients receiving gabapentin compared with the patients receiving placebo. Conclusion: Preoperative oral gabapentin reduced postoperative visual analogue scale scores, tramadol consumption and the occurrence rate of CRBD and nausea, and consequently, increased the degree of patients' satisfaction after transurethral prostate resection.