The conformation of traumatic diaphragmatic rupture is frequently difficult, even if radiologic evaluation has been performed. A 37-year old man with multiple trauma was suspicious with diaphragmatic rupture. The diaphragmatic rupture could not be confirmed with chest CT. We decided thoracoscopic operation for diagnosis. Diaphragm was ruptured about 8 cm length involving entering site of phrenic none into diaphragm and diaphragmatic paralysis was combined. We made 5 cm sized working window additionally. Ruptured diaphragm was repaired by continuous suture and plication of diaphragm was performed. Postoperative result was good at chest radiogram after three monthes.