X-linked adrenoleukodystrophy (X-ALD) is a peroxisomal disorder and identified in many races without apparent predilection for any race. This study was designed to investigate the clinical and therapeutic aspects of X-ALD in Taiwanese children with this disorder. We retrospectively reviewed all children admitted to NTUH from Nov. 1993 to Aug. 2002 with the diagnosis of ALD, defined by increased very long chain fatty acid (VLCFA). The mean age at diagnosis of the patients was 7.4 years (range, 2.8 to 13 years). Seven out of 9 patients had abnormal brain magnetic resonance image (MRI) studies. Three patients received bone marrow transplantation. Of these, two died of severe graft-versus-host disease and the other remained stable. Of the remaining 6 patients, two patients were in vegetative status and the other two patients were neurologically normal. X-ALD in Taiwanese children had similar clinical manifestations as reviewed in western countries. Symmetrical demyelination in parieto-occipital region and the accumulation of contrast material at the edge of the lesion are the typical MRI findings. Proton MR spectroscopy (MRS) can be used to evaluate either the asymptomatic patient or patient with normal brain image. Performance of T-cell depletion bone marrow transplantation or cord blood transplantation is suggested for X-ALD with early cerebral involvement.