A 57-year-old male patient was diagnosed with a left cerebellar infarction. He initially presented with unilateral sudden sensorineural hearing loss (SNHL) with long-lasting vertigo and spontaneous nystagmus to the left side, which were diagnosed using vestibular functional test tools and magnetic resonance imaging (MRI). MRI of the brain showed infarction in the area of the anterior and posterior cerebellar artery (AICA and PICA). Therefore, in patients with acute hearing loss and vertigo without obvious neurologic deficits, cerebellar infarction should be considered even if the patient is at low risk, as this can be the first sign of a life-threatening basilar artery thrombosis.