A 64-year-old man suffering from diabetes mellitus and chronic renal failure was admitted to our hospital because of consciousness disturbance and parkinsonism. Cranial MRI showed very characteristic features involving the bilateral basal ganglia. Subsequent postmortem examinations demonstrated demyelination in the affected areas. These myelin destruction patterns were quite similar to those of central pontine myelinolysis. However, rapid correction of hyponatraemia was ruled out in this patient. Therefore, a new demyelinating brain disease associated with diabetes mellitus and chronic renal failure was suggested.