PURPOSE: Ascorbic acid is a potent antioxidant capable of scavenging oxygen free radicals. We investigated the effect of ascorbic acid on initial management of a major burn. METHODS: A total of twenty two patients with extent of burn injury greater than 30% of the body surface area (BSA) were enrolled. Early fluid resuscitation was performed with Parkland formula (<40% BSA) and modified hypertonic formula (> or =40% BSA). In ascorbic acid group, ascorbic acid was continuously infused at a dose of 30 mg/kg/h during first 24 hours of fluid resuscitation. Target urine output was 0.5~1 ml/kg/h. RESULTS: There were no significant differences in age, sex, and BSA among the groups. In the cases of Parkland formula, there was no significant difference in the fluid requirement between control group (4.26+/-1.29 ml/kg/%burn) and ascorbic acid group (3.53+/-0.87 ml/kg/%burn). However, in the cases of modified hypertonic formula, there was significant difference in the fluid requirement between control group (3.31+/-0.95 ml/kg/%burn) and ascorbic acid group (2.34+/-0.35 ml/kg/%burn). CONCLUSION: High-dose ascorbic acid reduces fluid requirement at early fluid resuscitation in severely burned patients managed with modified hypertonic formula.