The Alzheimer's disease(AD)is a common neurodegenerative disease which threatening the life quality of elderly people.Complement system,which is a part of the innate immune system,plays an important role in neuroinflammation and neurode-generative diseases,and has a close relationship with the pathology,diagnose and treatment of AD.In this paper,the relevant resear-ches on the complement system and the pathological mechanism,biochemical markers and therapeutic methods of AD are reviewed,in order to provide new research,diagnosis and treatment directions for AD.