We report four siblings of a family with Alpers' disease. Three of four siblings occurred diarrhea and myoclonus at the ages of 7 to 8 years old. During the disease evolution, symptoms of subacute encephalopathy such as headache, visual disturbance, cortical blindness, progressive seizures and mental retardation were presented at the ages of 15 to 20 years old. Downhill progression led them to death in multiple organ failure within six to eight months of onset. CT showed hypodensity lesions in the bilateral oc cipital and temporal lobes. Spongiform changes, which characterized by diffuse neuronal degeneration or loss and astrocytosis, were most severe in the gray matter. White matter was slightly involved, while basal ganglia, pons, brain stem and cerebellum were not involved. Physical examination of the only live brother of the four siblings showed short status (165 cm), arched feet and improper nose-pointed test of the left side. Muscle biopsy of him showed a large amount of Red-Ragged (RR) fibers and abnormal mitochondria. Clinical features and pathological findings of autopsy in all the four siblings were consistent with progressive neuronal degeneration of childhood with liver disease (PNDC) - Alpers' disease. The muscle biopsy showed the characteristic findings of mitochondrial myopathy. Our report confirmed the classification of late onset Alpers' disease as a mitochondrial disorders.