BACKGROUND: Many strategies to reduce pain during propofol injection have been investigated. Inhibitors of cyclooxygenase are frequently used to provide post operative pain relief in patients undergoing minor gynecologic surgery. Therefore, in this study, we have investigated whether ketorolac injected intravenously reduces pain during propofol injection. METHODS: Fifty healthy female patients scheduled for minor gynecological surgery were randomly allocated to one of four groups. All patients were inserted 20 G Angiocatheter into the veins on the dorsum of the hands. After applying an arm tourniquet at an inflation pressure of 40-45 mmHg, the control group received 2 ml of 0.9% saline, and those in groups I, II, and III received ketorolac 0.5, 0.75, and 1.0 mg/kg mixed with 2 ml of 0.9% saline respectively. The tourniquet was released 2 minutes later. 2 mg/kg of 1% propofol bolus was then injected with an infusion pump intravenously. After 50 mg of propofol were injected, patients were assessed for visual analogue scale (VAS) scores and pain grades. RESULTS: VAS scores during propofol injection diminished significantly in group II (0.75 mg/kg ketorolac) and group III (1 mg/kg ketorolac) compared with the control (saline) group. CONCLUSIONS: Pretreatment with intravenous ketorolac more than 0.75 mg/kg during the 2 minutes tourniquet time can reduce pain elicited by profofol injection.