Objective To analysis and investigate the application of thorax low dosespiral CT in diagnosing of thorax trauma.Methods Selected 16 thorax trauma caseswho were treat in our hospital between Jun,2011 and Fer,2012.Diagnosed them by using routine X-ray thorax plain film and thorax low dose spiral CT scanning.Then compare the effect of the two methods.Results By using routine X-ray thorax plain film,it showed 14 cases were normal,and 2 cases were found local shadow of lung contusion.By using thorax low dose spiral CT scanning,it showed 10 cases werenormal,and 6 cases were found local shadow of lung rending.X-ray examination is about the inclined a took an average of 14.8 minutes.And low dose spiral CT scan chest in 20 seconds.Conclusion It is important and valuable to use thorax low dose spiral CT scanning in diagnosing of thorax trauma.