Recurrent cerebral infarctions developed in a patient with idiopathic thrombocytopenic purpura (ITP). At the time of the first stroke, there were large thrombi in the right proximal internal carotid artery (ICA) and an occlusion of the right terminal ICA. The occlusion was recanalized by intra-arterial infusion of urokinase. After 20 months, he suffered another ischemic attack. The autoantibodies in ITP directed against antigens presented on both platelets and endothelial cells might induce the endothelial damage, thrombus formation, and embolic occlusion of the artery.