Abstract: The causes of Alzheimer' s disease (AD) have not been fully elucidated, and the failures of the prevailing A beta theory in clinical trials make it more urgent to seek the causes of AD. Recent studies on AD have suggested that the dynamic balance between DNA methylation and demethylation might play an important role in early stages of AD pathology. Ten-eleven translocation proteins (Tets), an important protease family of DNA demethylation, are under extensive investigations on their roles in the progression of AD. In this paper, the implication of the DNA demethylation process regulated by Tet family in the progression of AD was reviewed, hoping to provide new ideas for the research on AD progression and the early diagnosis of AD.