A 22-year-old man, who had complained of dizziness and morning headaches, was admitted because of persistent polycythemia with elevated erythropoietin. Subsequently during the work-up, he had frequent sleep apneas without respiratory efforts and a brain MRI revealed multiple bilateral leukoencephalopathies without enhancement. Adrenoleukodystrophy was diagnosed by clinical manifestations including adrenal insufficiency, brain imaging, and an elevated very long chain fatty acids (VLCFA) level. We report a case of adolescent cerebral type of adrenoleukodystrophy presenting with central sleep apnea and secondary erythrocytosis.