Objective To investigate the risk factors of difficult defecation in earthquake victims. Methods A total of 192 earthquake victims suffering from difficult defecation who were transported to the field hospital of our hospital after earthquake were subjected in this study. Univariate analysis was carried out for 15 items of non-repetitive characteristic clinical factors which possibly caused difficult defecation. Logistic regression model was used for multivariate analysis. Results The results of univariate analysis showed that there were 8 risk factors for difficult defecation in earthquake victims(P＜0.05), including age, difficult defecation before injury, fractures, surgery or not, the posture influencing defecation, and the first time to eat, to return to normal diet, and to defecation after earthquake(P＜0.05). Logistic regression model for multivariate analysis indicated that age(P＜0.05), difficult defecation before injury(P＜0.05), surgery or not(P＜0.01), and the first time to defecation after earthquake(P＜0.01) were the independent factors for difficult defecation. Conclusion The independent factors for difficult defecation in earthquake victims are age, difficult defecation before injury, surgery or not and the first defecation time.