Background : A typical pupillary sign in internal carotid artery (ICA) dissection is miosis caused by Horner syndrome. Central retinal artery occlusion (CRAO) which causes afferent pupillary defect is rare in ICA dissection. Case Report : A previous healthy 20-year-old right handed woman was admitted due to sudden mental change and right hemiplegia. Funduscopic examination showed a cherry-red spot, suggesting CRAO. T2-weighted magnetic resonance imaging showed an increased signal intensity in the left middle cerebral artery territory, which was consistent with an infarction. Digital subtraction angiography revealed a typical“flame-shaped”narrowed occlusion of the left ICA. Conclusion : We present a young patient with ICA dissection who developed an afferent pupillary defect from CRAO, which is very rare in ICA dissection.