Alzheimer's disease (AD) is a neurodegenerative disorder characteristic of neurons reducing, senile plaques, neurofibrillary tangles and so on, and the most common cause of dementia among the elderly. Many efforts have been made to understand the epigenetic mechanisms involved in the development of AD, such as gene methylation and histone acetylation, although the exact mechanisms are not yet entirely clear. Here, we provide a review of the epigenetic mechanisms and related research in AD, which may provide a new direction for the research as well as the development of the epigenetic drugs.