Abstract: Objective To evaluate the decontamination efficacy of diphoterine for rat skin splashed by ammonia solution. Methods Titration curves in beakers and the neutralization efficacy were obtained by continuously measuring the pH of 1 mL 1 mol/L ammonia solution mixed with the different dosage of diphoterine with pH meter. The rat skin burned by 25.0% ammonia solution was then washed at 1,2 and 5 minutes after burning with 250 mL of saline solution,boric acid or diphoterine,respectively. Effects were assessed on the basis of changes in histological pathology examination of the burned skin at time 24 h post-exposure. Results Diphoterine was found to be a fast and efficient emergency decontaminant for the neutralization of ammonia solution in vitro. Rinsing with diphoterine,boric acid solution and normal saline were all efficient at 1 min after rat skin was burned by ammonia solution(F=0.462, P > 0.05). Diphoterine was obviously more efficient to reduce skin damage than boric acid solution and normal saline at 2 min after the skin was burned(q=-3.130, P < 0.05; q=17.441, P < 0.01),while no evident efficacy of the three solutions when they were used at 5 min after the skin was burned(F=0.412, P > 0.05). Conclusion The evident efficacy of cutaneous washing with diphoterine in time was proven by pathological demonstrations. Diphoterine proves to be efficient in the primary treatment of ammonia burns.