Kampo (Japanese herbal) medicines reharmonize imbalance of the body systems, therefore they recover whole body from unusual state to normal state by affecting neural, endocrine and immune systems. Because diseases of elderly people affect whole body, Kampo medicines seem to be suitable drug for their treatments. Alzheimer diseases and cerebrovascular disorders are popular dementia for the elderly people, and the former are characterized by memory loss and a progressive global impairment of intellect. Recent basic researches suggest that some Kampo formulas such as Toki-shakuyaku-san, Shimotsu-to, Kami-kihi-to and Kami-untan-to improve the lesion of cognitive function in the animal models for dementia. Kami-untan-to was also suggested to improve cholinergic disturbances via increasing effects of choline acetyltransferase and nerve growth factor. Some Kampo formulas have been applied clinically for the treatments of patients with Alzheimer diseases and cerebrovascular disorders. Choto-san is one of such examples, and it was proved the efficacy for the treatment of vascular dementia by double-blind controlled study. These observations suggest that some Kampo medicines are useful for the treatment of senile dementia. Although efficacy of Kampo medicines can not be explained by the pharmacological activities of a particular active principle, some active components in the formulas have been characterized.