PURPOSE: The pain related to burn is moderate to severe and difficult to control regardless of medications. We evaluated the effect of intravenous patient-controlled analgesia (IV PCA) with weight-compensated regimen of fentanyl and ketorolac in burn surgery. METHODS: consecutive 82 patients received IV PCA after burn surgery. They were divided into two groups according to total body surface area% (TBSA%): group I (TBSA> or =25%, n=21) group II (TBSA<25%, n=61). The IV PCA consisted of fentanyl (20 mcg/kg), ketorlac (3 mg/kg), and ramoserton (8.5 mcg/kg) and was programmed to basal infusion rate 2 ml/hr, bolus rate 0.5 ml, and lockout time 15 min. Pain score and satisfaction were evaluatedduring 4 study periods within 48 hours after end of surgery: 0~6 h, 6~12 h, 12~24 h, and 24~48 h. Added recue drugs were evaluated at each interval. RESULTS: Improvement of pain score during study periods was significant in both groups (P<0.001). However, Group I showed significantly higher VAS score than Group II. Frequency of rescue drug use was significantly higher in Group I than Group II. Improvement of satisfaction score in group II were significant (P<0.001). However, there was no significant difference in satisfaction score between two groups. CONCLUSION: The pain of burn (TBSA> or =25%) was difficult to control by conventional IV PCA, even through weight-compensated regimen. Pain of burn (TBSA> or =25%) should be controlled by increased dose of analgesics and approaches other than conventional medication.