We describe a rare case of sudden onset of unilateral sensorineural hearing loss occurring as the first symptom of moyamoya disease, which is characterised by progressive stenosis of the intracranial internal carotid arteries and their proximal anterior cerebral arteries and middle cerebral arteries. Case report and review of the world literature regarding moyamoya disease with hearing loss. The reported patient had moyamoya disease that initially presented as sudden, unilateral sensorineural hearing loss. Magnetic resonance imaging showed occlusion of the anterior cerebral, middle cerebral and distal internal carotid arteries bilaterally. The possible mechanism of this patient's sudden sensorineural hearing loss may have been vascular occlusion resulting from thrombotic narrowing or blockage by plaque. The described patient represents the first reported case of sudden onset, unilateral sensorineural hearing loss occurring as the first symptom of moyamoya disease. The possibility of a vascular lesion such as moyamoya disease should be considered in patients with sudden sensorineural hearing loss, especially children, young adults and Asian patients. Due to this disease's poor outcome, early diagnosis and treatment are important to prevent stroke.