Objective: To verify the moisture maintaining effect of moist exposed bum ointment (MEBO) in treating burn wound. Methods: Rabbit model with Ⅱdegree burn wound was used in this study. Observations were conducted at 0 (before burn), 0. 5, 6, 24, 48, 72, and 168 hours postburn. The data of wound water evaporation, wound appearance and pathological changes of the wounds were compared with that Of the bum wounds treated with Vaseline or conventional dry exposed therapy. Results: It was found that wounds treated with MEBO had water evaporation close to that of normal skin and was significantly less than that of the wounds treated with dry exposed therapy (P<0. 01). MEBO did not obstruct water evaporation from wound as Vaseline did (P<0.01). Wounds treated with MEBO had good permeability and adequate drainage. Conclusion: MEBO provided the wounds with a physiological moist environment.