Alzheimer disease （AD） is a neurodegenerative disease， which is the most common type of dementia. At present， the pathogenesis of AD is still unclear， and it is difficult to develop new drugs. For many years， the strategy of "one molecule， one targe" has been used to treat AD， but the effect is not ideal. In other diseases such as cancer， AIDS and tuberculosis， multi-target drug combination therapy has shown good clinical benefits， while the drug combination therapy for AD is still in its initial stage. Thus， in this paper， the research progress is summarized from the mechanism of action.