Objective:to find suitable method for detecting Alu methylation in large samples of tumor tissues and tumor cell lines. Methods:Methylation-sensitive restriction endonuclease digestion and quantitative PCR(MSRE-qPCR)method were used to analyze Alu methylation in MCF-7 breast cancer cells and compared with the traditional bisulfite-sequencing PCR(BSP)method. Results:MSRE-qPCR showed that methylation level of Alu elements in BstUⅠ cutting site was about 33.7%,and that in HpaⅡ cutting site was about 56.1%. The result of MSRE-qPCR was consistent with that of BSP,which also showed relative lower level of Alu methylation in BstUⅠ cutting site and relative higher level of Alu methylation in HpaⅡ cutting site. Methylation levels of Alu elements in MCF-7 cells detected by the two methods were all lower than those in normal cells(84.6% or higher). Conclusion:MSRE-qPCR method is simple,reliable and inexpensive enough for Alu methylation detection in large samples.