A 46-year-old man developed acute-onset right cervical internal carotid artery occlusion at its origin, and concomitant multiple visceral artery aneurysms were also detected during the evaluation of cerebral infarction. Follow-up cerebral angiography confirmed the irregular and beaded appearance of the right cervical internal carotid artery, presumably secondary to dissection. The clinical and radiological findings in the patient were most consistent with segmental arterial mediolysis, and we considered that segmental arterial mediolysis might be the cause of internal carotid artery dissection. The typical presentation of segmental arterial mediolysis is acute fetal intra-abdominal hemorrhage as a result of dissection of visceral artery aneurysms. Hence, physicians should be aware of segmental arterial mediolysis in the differential diagnosis of internal carotid arterydissection and carefully assess the application of thrombolytic therapy.