Objective To observe and analyze the correlation between the DNA methyltransferase-3B (DNMT3B) gene single nucleotide polymorphisms (SNP) rs 1569686 and the susceptibility to colorectal cancer (CRC) in Tianjin Han population.Methods A case-control study was performed.89 CRC patients and 94 normal controls were examined,and Sequenom MassArray system was applied to detect the genotype of rs1569686 in DNMT3B gene polymorphisms.The association results were analyzed of the SNP and CRC.Results The frequencies of genotypes TT,GT and GG at SNP rs1569686 were 74.2％,24.7％ and 1.1％ in CRC patients respectively,which there were no significant differences from that in controls(73.4％,23.4％ and 3.2％; P＞0.05).Conclusion It suggests that the SNP rs1569686 of DNMT3B gene may not be related to susceptibility of CRC in Tianjin Han population.