Abstract: Objective To analyze the effect of high temperature（HT） and high humidity（HH） environment on traumatic cerebral edema（TCE） by studying the influence of HT and HH environment on cerebral water content and AQP4 expression in rats with cerebral injury. Methods Sixty-four healthy adult male SD rats were randomly divided into normal temperature（25℃） group without traumatic injury（n=16）,normal humidity（RH 50%） group with traumatic injury（n=16）,HT（35℃） and HH（RH 85%） group without traumatic injury（n=16）,and HT（35℃） and HH（RH 85%）group with traumatic injury（n=16）.An acute cerebral injury model of rats was established with the free-falling body method.6 and 24 hours after the rats in 4 groups were killed,cerebral water content and expression of AQP4 protein and mRNA were detected by electron microscopy with HE staining. Results The expression level of AQP4 and AQP4 mRNA and cerebral water content were significantly higher in normal temperature group with traumatic injury than in HT and HH groups with traumatic injury（P＜0.01）. Conclusion HT and HH environment can exacerbate TCE.