Abstract: The Apolipoprotein E（ApoE）gene plays important roles in the research of the Alzheimer disease (AD). It has been clear that apoE gene is closely related with dementia in the elderly. In recent years, extensive researches regarding the relationship between ApoE gene polymorphism and AD has been conducted in general population as well as patients with AD using molecular biology technique. The writer reviewed the progress on this field hoping to provide some fundamental information for the related research in AD.