A 13-year-old boy was admitted via emergency room with dyspnea after vigorous coughing. Subcutaneous emphysema was palpated on both eyelids and around the neck. Breathing sound was slightly wheezy. On initial chest roentgenogram no parenchymal lesion or pneumothorax except subcutaneous emphysema on the thoracic wall was found. On the second day of hospitalization he showed agitation much more severe than the roentgenographic findings on the chest. Diffuse severe subcutaneous emphysema, pneumomediastinum, pneumopericardium, retroperitoneal pneumoperitoneum and epidural emphysema were found on computed tomography. He did not showed neurologic deterioration or respiratory difficulty demanding mechanical ventilation. He was treated with oxygen, bronchodilator and corticosteroids. After four days of hospitalization, tension pneumothorax finally developed which was successfully treated by closed thoracic tube drainage with water sealed bottle. The patient recovered without any sequelae after conservative care. On the follow up computed tomography no underlying pathologic lesion or residual emphysema was found.