The authors report a case of Menkes' syndrome, probably the first one described in Brazil. The patient, a 15-month-old boy, showed pili torti, early progressive psychomotor deterioration and seizures. Serum levels of ceruloplasmin and copper were very low. Neuroradiological and roentgenological examinations revealed diffuse cerebral atrophy, arterial changes and bone abnormalities. At the post-mortem examination the more consistent findings were cerebral atrophy, neuronal loss in the thalamus and above all cerebellar cortical lesions. The disease has a sex-linked recessive inheritance and is believed to be caused by an inborn error of copper metabolism, perhaps subordinated to changes of proteins which carry copper to different tissues. The relevant literature in relation to the pathogenesis is reviewed.