The authors report the case of a 51 year-old man who developed a carotid-cavernous sinus fistula after a blunt trauma. In view of an exophthalmia, an impressive chemosis, a pupillary dilatation due to parasympathetic paralysis and a bruit over the right orbit, a carotid-cavernous sinus fistula was diagnosed. The existence of the fistula was confirmed by a brain CT scan and a cerebral angiogram. Carotid-cavernous sinus fistulas are rare. They are spontaneous or posttraumatic. Cerebral angiography is the diagnostic procedure of choice. The authors review the signs and symptoms, diagnostic procedures, treatment, and prognosis of this complication.