Pneumomediastinum can result from fractures involving paranasal sinuses, orbits, mandibles, other facial bones. This is a case report of an 25-year-old man who fell from a third floor. He suffered injuries to the maxillofacial region. Initial examination revealed a mandibular complex fracture and tooth loss, but the man developed neck swelling, dyspnea, and dysphagia over the next 3 days. Repeat examination revealed marked pneumomediastinum and subcutaneous emphysema.