This case study reports the audiological and surgical findings for a nine-year-old boy with an acoustic neurinoma. He was suspected of having a right ear retrocochlear lesion following three audiological evaluations in four years. The initial evaluation indicated normal hearing ability. The second and third evaluations indicated a progressive right ear hearing loss, characterized by reduced word discrimination ability and absent acoustic reflexes. The patient had a 5 cm acoustic neurinoma compressing and adherent to the brain stem. The tumor was successfully removed following three operations employing an otoneurological and neurosurgical team approach through a retromastoid exposure. Postoperative recovery was uneventful. Facial nerve function was not disturbed, however attempts to preserve hearing on the involved side were not successful.