[目的]了解汶川地震后灾区儿童创伤后应激障碍(PTSD)现状,并分析其影响因素。[方法]按照分层随机抽样方法的原则抽取253例调查对象,通过Bootstrap再抽样方法扩大样本量至2000例,在对资料进行描述性分析的基础上,通过SAS Enterprise Miner软件和决策树C4.5算法建立决策树模型,分析儿童患PTSD的影响因素。[结果]对儿童是否患PTSD建立决策树模型,其对训练集,验证集,测试集有分类错误率分别为0.070,0.100,0.075,按重要性排序筛选出汶川地震后影响灾区儿童患PTSD的7个影响因素。[结论]决策树C4.5算法建立的模型效果较好。针对地震后灾区儿童患PTSD的主要影响因素,采取相应的措施,有助于降低儿童患PTSD的比例。 [Objective] To understand the current situation of post-traumatic stress disorder (PTSD) in children affected by the Wenchuan earthquake and to analyze its influencing factors. [Methods] According to the principle of stratified random sampling, 253 samples were selected, and the sample size was expanded to 2000 with Bootstrap resampling method. Based on the descriptive analysis of the data, SAS Enterprise Miner software and decision tree C4 were used. 5 algorithm to establish a decision tree model to analyze the influencing factors of PTSD in children. [Results] The decision tree model of children with PTSD was established. The classification error rates of training set, verification set and test set were 0.070, 0.100 and 0.075, respectively. The PTSD of children affected by Wenchuan earthquake was screened by importance 7 factors. [Conclusion] The model established by decision tree C4.5 algorithm works better. Aiming at the main influencing factors of PTSD in children affected by earthquake and taking corresponding measures, it will help to reduce the proportion of PTSD in children.