A case of a small left pontine tegmental hemorrhage that presented as cheiro-oral syndrome with a bilateral perioral sensory disturbance is described. An 83-year-old man suddenly developed numbness in his bilateral perioral area and right hand. Head CT and MRI (T(2)*-weighted image) revealed a small left pontine tegmental hemorrhage. The patient was diagnosed as having cheiro-oral syndrome with bilateral perioral sensory disturbance, probably due to unilateral pontine tegmental hemorrhage. All residual symptoms disappeared within a month.In the present case, the following clinicopathological hypothesis was considered. The hematoma located in the left pontine tegmentum impaired the sensory fibers from the contralateral medial lemniscus (from the right hand) and the ventral trigeminothalamic tract (from the right perioral region). In addition, the ipsilateral trigeminothalamic tract (from the left perioral region) was also impaired. It is important to know that a small unilateral lesion in the brainstem (especially the pons) can cause cheiro-oral syndrome with a bilateral perioral sensory disturbance, and a small brainstem hematoma is the most frequent etiology of this disease.