Wallenberg syndrome(lateral medullary syndrome) is the result of the occlusion of the posteroinferior cerebellar artery or the vertebral artery itself. The syndrome consists of nystagmus, vertigo with nausea or vomiting, loss of pain & temperature sensations in the ipsilateral face, ipsilateral Horner syndrome, ataxia, dysphagia & loss of pain and temperature sensatons in the trunk and limbs except the face. The author reports with the review of literature a case of wallenberg syndrome in which typical clinical symptoms were shown and serration due to thromotic plaque was noted at the origin of basilar artery from vetebral artery on 4 vessle angiogram.