Background: Preemptive analgesia has been suggested recently as an another technique of postoperative pain control. Combination of low dose opioid and NSAIDs was used to lessen systemic opioid side effect, however, the use of NSAIDs may hinder their side effects in perioperative period. The local application of small dose at the target site can be effective without systemic effect. The aim of this study is evaluating the additive effect and side effect of transdermal piroxicam as preemptive adjuvant to intravenous nalbuphine on pain relief after major abdominal surgery. Methods: We reviewed the records of patients received piroxicam patch for preemptive analgesia before operation and compared it with control group. Two sheets of piroxicam patch to the skin incision site for 12 hours before operation were attached (Group 1, n=20) and no patch were applied (Group 2, n=20). Both groups were received nalbuphine continuously after operation using two days infuser (2 ml/hr) containing 80 mg (96 ml). Pain is evaluated by VAS score at each time; 30 min, 1, 6, 12, 24, 36, 48 hours after operation and side effects of NSAIDs were observed for 3days postoperatively. Results: There was no significant VAS score difference between two groups following time in progress. And no significant side effect was noted in both groups, either. Conclusion: There is no preemptive or synergistic analgesic effect of piroxicam patch attached at planned operation site before operation.