Objective： Explore the relationship between Alzheimer's disease （AD） and daily diet， provide scientific dietary guidance， and reduce the risk of AD. Methods： A case-control study was conducted. The elderly who were over 65 years old and without cerebrovascular diseases from 66 old folks' home in 9 administration bureau of Heilongjiang Land Reclamation Authority was selected as the subjects. The total number of this survey was 664， among the respondents， AD patients （case group） accounted for 256， and control group accounted for 408. Questionnaire professionally designed was used. Results： Elderly with higher levels of education and non-living alone， causing the lower risk of suffering AD. Often paying attention to diet control [OR=0.473（0.247-0.906）]， daily staple uncertain [OR=0.425（0.256-0.707）]， occasionally eat fish [OR=0.433（0.261-0.719）] and fruit [OR=0.457（0.237-0.881）] were less likely to suffer AD. Aluminum contact and grilled food： Those often/daily used aluminum tableware （OR=3.995）， ate barbecue food （OR=2.266） were more likely to suffer AD. Conclusion： Dietary habits is an important factor of AD. The elderly should be promoted to avoid excessive intake of animal fat， eat more fresh fruits and fish.