A 60-year-old man with hypertension presented with an acute onset of an isolated sudden deafness with vertigo. On admission, initial brain MRI, including diffusion images, was normal. During admission, the patient presented with an exacerbation of vertigo. A follow-up MRI revealed new infarcts involving the right middle cerebellar peduncle, the right dorsolateral pons, and right anterior cerebellum. In this patient, an acute onset of an isolated sudden deafness with vertigo may be a heralding manifestation of the pontocerebellar infarction.