Subcortical vascular dementia (SVD) exhibits relatively uniform clinical and pathological features among various subtypes of vascular dementia, and constitutes approximately half of vascular dementia in Japan. This subtype is further classified into Binswanger's type infarction and multiple lacunar infarctions. The former is characterized by diffuse white matter lesions, and the latter by lacunar infarctions. However, the both have common pathologic mechanism related to hypertensive small vessel changes. This paper overview the notion, clinical features, pathogenesis and treatment for SVD, and also refer to the recent topics related to Alzheimer's disease.