Penetrating injuries to the superior caval vein (SCV) are rare but are very serious. They can be associated with hemodynamic instability and often produce a substantial technical challenge to the surgeons. We report a case of 32-year old man who was admitted to our hospital having sustained multiple stab wounds over the right chest wall and extremities. Many victims of penetrating thoracic trauma with SCV injury are in profound shock, whereas our patient on arrival in the emergency department had a stable condition, so the diagnosis was delayed. We consider that associated mediastinal pleural adhesions confined the bleeding into the mediastinum which prevented prompt massive bleeding. Therefore he tolerated a preoperative delay of six hours. Caval injury should be kept in mind in the differential diagnosis of hemothorax.