We report a patient whose clinicopathological findings are compatible with those of the case reported by Menzel in 1891. This case was briefly reported by Kinoshita et al in 1967 as hereditary ataxia of Menzel type. But the concept of this disease has been confused, especially in the early investigations for the hereditary olivo-ponto-cerebellar atrophy (OPCA) in Japan. The Kinoshita's patient should be considered as the first Japanese case whose findings are identical with Menzel's report. This report represents a precise study of the case reported by Kinoshita et al. The patient was a 42-year-old Japanese woman. Her mother and one of her brothers suffered from the same disease. She began to experience progressive ataxia at the age of 30. At age 42, she was admitted to another hospital because of inability to walk and mental deterioration. Neurological examination revealed cerebellar ataxia in the extremities and trunk, childish personality change, dementia, diminished deep tendon reflexes with extensor plantar response bilaterally, slowness and hypokinesia in the movement, generalized muscular atrophy, and sensory disturbance prominent in deep sensory. She had no involuntary movement and dysautonomia. She had no retinal degeneration, nystagmus, nor progressive nuclear oculomotor palsy. She died of pneumonia. Neuropathological findings revealed brain weight of 850g.(ABSTRACT TRUNCATED AT 250 WORDS)