A successful repair of traumatic descending thoracic aorta rupture was performed in a 27 year old man. The patient had automobile accident and transferred to our hospital. On admission, a chest film showed mediastinal widening and soon aortography was done. There was a fusiform aneurysm on the descending thoracic aorta just distal to the origin of the left subclavian artery measuring 5cm in diameter and 7cm in length. He underwent thoracotomy and the injured part of the aorta was replaced with a 24mm tightly Woven Dacron graft using femora-femoral bypass. The postoperative course was uneventful.