Abstract: Objective To study the changing rules of telomere methylation in patients with Alzheimer’s disease（AD）. Methods Distribution of telomere methylation in peripheral blood of 39 patients with AD and 57 healthy controls was detected with restriction endonucleases MspI and HpaII. Results The average length of telomeres detected with MspI and HpaII in patients with AD and in healthy controls was not significantly different but negatively related with the age of patients with AD.The methylation extent of the longest telomere（＞9.4kb） and the shortest telomere（＜4.4kb） was significantly higher in patients with AD than in healthy controls（0.28±0.16 vs 0.22±0.12,P=0.021,0.24±0.11 vs 0.46±0.15,P＜0.001）. Conclusion Accelerated methylation of telomeres in patients with AD is their aging-related features.