Diagnosis of diaphragm injuries is difficult due to the absence of specific symptoms and clinical vigilance to identify this pathology especially when the fact of its damage was not recorded in the acute period of injury. The modern treatment concept assumes only surgical treatment of post-traumatic diaphragmatic hernia and the operative access and the choice of the optimal volume of intervention provides an individual approach. A single-stage videothoracoscopic correction of chronic post-traumatic left-sided diaphragmatic hernia and giant bulla of the left lung is presented. A diaphragmatic hernia was detected in a 56 years old man 30 years after a stab wound to the chest and abdomen, left thoracotomy and laparotomy. In the etiopathogenesis of this rare post-traumatic true diaphragmatic hernia lays the tangential injury to the abdominal obstruction with damage only of the pleural leaf and the muscular layer of the diaphragm where the remaining intact diaphragmatic peritoneum gradually stretches and forms a hernial sac. The presented clinical observation indicates the difficulties of diagnosing diaphragm injuries in concomitant injury. If indicated the videothoracoscopic operations can effectively eliminate a diaphragmatic hernia and, if necessary, simultaneously perform surgical intervention on an adjacent organ.