A 66-year-old woman had a unilateral infarction in the cerebellar peduncle. Saccadic eye movements were intact in this patient, while smooth-pursuit eye movements were impaired. Magnetic resonance imaging disclosed that the lesion was well localized in the superior cerebellar peduncle and the juxtar-estiform body. These findings support the idea that saccade signals from the cerebellum project to the brainstem through the hook bundle which was recently confirmed in the monkey.