This paper reports a rare case in which a development and improvement of post-traumatic stenosis of the internal cartoid artery was documented by angiographical studies. A 31-year-old male suffered from disturbance of consciousness with left hemiparesis following head trauma. On admission, plain craniograms showed fracture of the bilateral vertex and a fracture crossed the right carotid canal. Right carotid angiogram revealed that the internal carotid artery was visualized "striped" and its wall was irregular narrowing. Angiogram taken nine days after the trauma showed an improvement of the stenosis. Consciousness disturbance and neurological signs had gradually improved by the end of the fourth post traumatic month. In the follow-up angiographical study, six months after the injury, the stenosis of internal carotid artery was found greatly improved.