Spontaneous rupture of the pulmonary alveoli after a sudden increase intra-alveolar pressure is a common cause of pneumomediastinum, which is usually seen in healthy young men. Other common causes are traumatic and iatrogenic rupture of the airway and esophagus; however, pneumomediastinum following cervicofacial emphysema is much rarer and is occasionally found after dental surgical procedures, head and neck surgery, or accidental trauma. We present two cases of pneumomediastinum following cervicofacial subcutaneous emphysema after oral trauma. They constitute an uncommon clinical entity, So its radiologic appearance, clinical presentation, and diagnosis are described.