Objective:To investigate the association between methylenetetrahydrofolate reductase (MTHFR) 677C/T polymorphism and Alzheimer’s disease(AD). Method:A meta-analysis including 1 048 cases and 1 220 controls in eligible studies were performed. The odds ratio(OR) of genotype and allele frequencies were regarded as statistics value, a random-effect or fixed-effect model was used in the analysis, and publication bias was assessed. Results:Nine papers met the criterion and were included in the meta study, and no significant publication bias was showed. The OR(95%CI) values of T/C and(TT+TC)/CC were 1.21(1.07~1.37) and 1.44(1.07~1.93). Conclusion:The MTHFR C677T polymorphism is associated with AD.