Tension pneumopericardium is a rare complication of gunshot wounds. A 28 year-old male patient with tension pneumopericardium after chest trauma by gunshot bullet injury was reported. On initial examination, hemopneumothorax and fracture of the clavicle were found on the right side. Interestingly, there was no image of additional pneumopericardium on telecardiogram at the admission to the hospital. Following right tube thoracostomy, 900 ml of blood and some air were drained. Due to additional 400 ml blood drainage on the second day, right thoracotomy was performed. Laceration of the right lung and the bleeding from the right innominate vein were sutured. There was no visible pathology on pericardium. Tension pneumopericardium occured on the second day of admision and a tube was inserted in to the pericardial space through subxyphoid incision. No blood but some air was drained from pericardial space. After removing the pericardial and right thorax tubes on the fifth and sixth days respectively, the patient was discharged with complete recovery.