We experienced 2 cases of surgical immobilization with Judet`s strut for flail chest with multiple rib fractures. The patients were undertaken explorative thoracotomy for unevacuated hematoma and chest wall fixation for paradoxically moving segments of ribs after initial trials of internal fixation, i.e. mechanical ventilation with endotracheal intubation. Immediately after operation, the patient`s general condition and respiratory status were improved remarkably. Mechanical ventilation and endotracheal intubtion were removed on postoperative second day without any events.