Pneumomediastinum in patients with war injuries to the maxillofacial region can be a life-threatening condition. A case is presented of a flare-pistol-shot wound to the mandible which subsequently resulted in cervical emphysema, mediastinal emphysema, and pneumomediastinum, causing a critical condition. Maxillofacial surgeons should be alert to this problem when treating blast or multiple-shell injuries to the maxillofacial region.