Hearing loss and blindness rarely occur in patients with chronic myeloid leukemia (CML). In this article, we present a 12-year-old girl who had right-side hearing loss as the initial manifestation of CML, followed by left-side hearing loss and blindness of the left eye several days after initiating treatment. The initial white cell count was 181,700/mm3. Audiometry showed severe sensorineural hearing loss of her right ear and moderate mixed hearing loss of the left ear. An ophthalmic examination showed optic neuropathy with subhyaloid hemorrhage in the left eye. A brain magnetic resonance image showed minor hemorrhaging in the right lower frontal area and anterior thalamus. These findings might have implied leukostasis with hyperviscosity syndrome. She died on the 9th hospital day. This case illustrates that CML should be considered 1 of the rare diagnoses in a patient with sudden onset of hearing loss.