The most common early symptoms of acoustic neuroma are unilateral progressive sensorineural hearing impairment and tinnitus. Acoustic neuroma presenting as acute vertigo is less often. We experienced a case of acoustic neuroma with the chief complaint of acute vertigo for 8 days in May 1993. Decreased caloric response and abnormal auditory brainstem response were noted. A 2 × 2 cm tumor mass in the left cerebellopontine angle was detected by MRI. It was proved to be an acoustic neurilemmoma after surgery.