Recent researches show that Alzheimer’s disease (AD), like other common chronic diseases, develops as a result of interaction of multiple factors rather than a single cause. This article reviewed some factors that can increase the risk of AD, such as age, smoke, genetic mutations, apolipoprotein E (APOE)-ε4 gene, cardiovascular and cerebrovascular diseases, type 2 diabetes mellitus and traumatic brain injury. We aimed to discuss their roles in the development of AD, and thus provide a foundation for prevention and treatment of AD.