CT findings and complete clinical data of 185 cases with closed chest injuries were retrospectively analyzed.The diagnosis of 185 cases were pulmonary contusion ( n = 185 ),pulmonary laceration ( n = 35 ),Macklin effect ( n = 5 ) and lung herniation ( n = 1 ).CT findings of lung contusion appeared as thick and vagur lung marking (n =9),small points shadows (n = 12 ),blotchy shadows (n =48),small pieces shadows (n=10),ground-glass shadows (n=16),large pieces shadows (n =5),diffuse patchy clouding shadows (n = 17) or mixed lesions (n = 68).CT appearance of lung laceration included pulmonary hematomas (n = 12),cavitary lesions with air ( n = 19),cavitary lesions with air-fluid levels ( n = 53 ).Macklin effect appeared as bronchus-,pulmonary vessel-adjacent air collection and mediastinal air collection (n=5).Traumatic pulmonary hernia appeared as lung herniation through an intercostal space.Initial CT scan missed one case of pulmonary contusion and 2 cases of pulmonary laceration. Key words: Thoracic injury,closed; Tomography, X-ray computed