Alzheimer's disease is a neurodegenerative disorder, characterized by progressive decline in memory and in social performance. The morphological hallmarks of the disease are neuronal loss, loss of dendritic spines, neurofibrillary degeneration and neuritic plaques mainly in the hippocampus and the cortex of the cerebral hemispheres. This study is based on the morphological analysis of the cerebellar cortices of eight brains, 4 patients suffered from Alzheimer's disease and 4 normal controls, by Golgi method, as well as Nissl, Gallyas', Bielschowsky's, Methenamine Silver staining and Congo red methods. Although typical neuritic plaques were not seen in the cerebellar cortex and the diffuse plaques found in the cerebellum in far smaller proportion than plaques in the prefrontal and parietal cortices of the same cases, Golgi impregnation technique revealed a loss of Purkinje cells and a marked decrease in the density of dendritic arborization.