The frequency of vertebral artery aneurysm is rare and a common presenting sign is subarachnoid hemorrhage. Lateral medullary syndrome is characterized by loss of pain and temperature sensation on the contra lateral lesion side of the body and ipsilateral lesion side of the face, dysphagia, dysarthria, ataxia, vertigo, nystagmus, and Horner syndrome. Vertebral artery dissecting aneurysm is a common cause of lateral medullary infarction. We present a rare case of a 46-year old male patient that developed ischemic attack presenting as transient lateral medullary syndrome due to thrombosed-fusiform aneurysm of vertebral artery. He was treated with aspirin and heparin, and then discharged with complete resolution of symptoms.