Objective：To investigate the relationship between age and the methylation of CpG loci，which is in the neuronal pentraxin Ⅱ（NPTX2） gene’s promoter region. Methods：Genomic DNA was extracted from 170 cases of peripheral blood samples of living，and then modified by methylation modification kit. The NPTX2 gene promoter methylation status was detected by the methylation spe－cific-PCR（MSP） method，and its relationship with gender，age was analyzed. Results：Age and sex of each sample were taken as inde－pendent variables while whether having methylation was taken as dependent variable. Binary logistic regression analysis showed that statistical significance was not found between whether having methylation and gender factor（P=0.843），suggesting that gender does not affect NPTX2 gene methylation；and statistical significances were found between whether having methylation and age factor（P=0.000），suggesting that age factors significantly influences the gene methylation. Taking five-year-old as an age group，linear re－gression analysis revealed that there were linear relationship among male（P=0.001），female（P=0.000） and the overall（P=0.000），indi－cating that methylation rate is linearly increased with the increase of age. Conclusion：The methylation rate of NPTX2 gene promot－er increased with age. Further research may establish a regression model for age estimation.