Tracheobronchial rupture is a rare and serious complication of blunt chest trauma. The cause is often a traffic accident and the rupture may be associated with other, fatal injuries. Three cases were treated at our clinic in the period 1970-1982. In them, as in about 60% of all cases in the literature, the tracheobronchial injury was not recognized in the acute stage. The early clinical picture may vary, depending on the site and extent of the injury, from only minimal mediastinal emphysema to severe dyspnea with extensive subcutaneous and mediastinal emphysema or persistent pneumothorax. The correct diagnosis was confirmed in all three of the described cases by bronchoscopy, which was performed in the late course because of respiratory difficulties and roentgenographic evidence of pulmonary complications. Since early surgical repair is essential for a good functional result, the possibility of tracheobronchial rupture must be kept in mind in any case of severe thoracic trauma.