Objective To investigate the prevalence rate and the related risk factors of posttraumatic stress disorder ( PTSD) in the rescue paratroopers 1.5 year after Wenchuan earthquake. Methods A total of 183 rescue paratroopers who participated in disaster rescue after Wenchuan earthquake were investigated with the questionnaires composed by General state of health questionnaire, PTSD Checklist-Civilian Version ( PCL-C), Symptom Checklist-90 ( SCL-90), Self-Rating Depression Scale ( SDS) and Eysenck Personality Questionnaire (EPQ). Results Six rescue paratroopers had total PCL-C score ≥ 38 points, with the prevalence rate of PTSD for 3.28%. Total PCL-C score was positively correlated with total SCL-90 score, N score of EPQ and total SDS score (P ＜ 0. 01), but negatively correlated with E score of EPQ. Total PCL-C score showed statistical difference between injury group and uninjury group, family loss group and family integrity group, contacting corpses group and none contacting corpses group (P＜0.05 or ＜0.01). Regression analysis showed the length of military service, nervousness, family loss by earthquake, suffering injuries or contacting corpses during relief operations were the risk factors for PTSD. Conclusion The prevalence rate of PTSD in the rescue paratroopers is higher than that in normal troops (0.49% ) 1.5 year after Wenchuan earthquake, indicating that further attention should be paid to the rescue paratroopers in later period after earthquake.