A 52-year-old man with no apparent family history of neurodegenerative diseases developed gait disturbance at age 47. Neurological examination at aged 52 revealed spastic paraplegia, generalized hyperreflexia, decreased of vibration sense in the lower limbs, and pollakisuria. Ocular symptoms, deafness, cerebellar ataxia, extrapyramidal signs, mental deterioration, dementia, peripheral neuropathy, retinal pigment degeneration, ichthyosis and syndactyly were absent. MRI of the brain was normal. A pure form of hereditary spastic paraplegia was diagnosed. Genetic analysis revealed a novel missense mutation in the spastin gene (1207C --> G, P361R). The clinical features of this patient were consistent with those of patient with the pure form of SPG4. Gene analysis should be considered for patients with spastic paraplegia even in the absence of any family history.