Late onset sporadic cerebellar ataxia with myoclonus is a rare autosomal dominant inherited disease. Beginning at ages between 40-50 years, brisk tendon reflexes and increased muscle tone in limbs, poor coordination of hands, intention tremors, extensor plantar reflexes with cerebellar ataxia which is the prominent manifestation are clinical features of this disease. A patient with the diagnosis of late onset sporadic cerebellar ataxia was evaluated according to the clinical and electrophysiological findings.