Abstract： Objective To investigate the possible correlation between the monocyte chemoattractant protein-1 ( MCP-1 ) gene A-2518G single nucleotide polymorphism (SNPs) in the promoter region and acute coronary syndrome (ACS) in Chinese Han ethnic population of Sunan region,Methods This study was conducted with a case-control design in 484 ACS patients including 290 acute myocardial infarction (AMI)patients and 194 patients with unstable angina pectoris (UAP) and 346 control subjects ruled out coronary disease by coronary angiography (control group),including 166 patients with coronary atherosclerosis and 180 subjects without coronary stenosis.Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used for the detection of the A-2518G polymorphism in MCP-1 gene,and then thefrequency of genetype was statistically analyzed.Results There were AA,AG and GG genotypes of MCP-1 gene A-2518G polymorphism in the ACS group and control group.The two groups could be considered as a genetic equilibrium representative by Hardy-Weinberg equilibrium ( P ＞ 0.05 ).Compared with the control group,the frequencies of AA genotype ( 15.32％ vs.16.12％ ),AG genotype (53.47％ vs.51.86％ ),GG genotype (31.21％ vs.32.02％ ) and G allele genotype (57.95％ vs.57.95％ ) in ACS group were not significantly different ( P was 0.083,0.673,0.821 and 1.00,respectively).Multivariate logistic regression analysis indicated that there was no significant correlation between MCP-1 gene A-2518G polymorphism and ACS regardless of differences in gender,age,smoking,diabetes,TG and LDL-C ( P ＞0.05 ).There was no significant difference in gender and age of ACS onset between two groups ( P ＞ 0.05).There were no significant differences in the frequencies of AA,AG and GG genotypes and G allele genotype among AMI group,UAP group and normal coronary group ( P ＞ 0.05).Conclusions The data shows that MCP-1 gene A-2518G polymorphism is not associated with the risk of ACS in the Chinese Han ethnic population living in Sunan region.