Aim To investigate the relationship between connexin37(CX37) gene I1297D polymorphism and premature coronary heart disease(CHD) in Chinese Han population. Methods CX37 genotype was examined with the methods of polymerase chain reaction and restriction fragment length polymorphism(PCR-RFLP) in 196 patients with CHD and 218 Chinese healthy individuals as control diagnosed by angiogram. Results The results showed that CX37 ID genotype in CHD group and CX37 II genotype in control group were dominant genotypes respectively.The DD genotype and D allele were rarity in both groups.The genotype frequencies of II,ID and DD were 44.39%,47.45% and 8.16% in patients with CHD,47.71%,44.04% and 8.25% in the controls respectively,and no difference was found between CHD and healthy subjects(χ2=0.51,P=0.77).CX37 I allele in the population was significantly higher than D allele,while the distribution of allele frequency was similar between the patients and controls(68.11% vs 69.72%,P=0.62,Or=0.93,95%CI=0.70～1.24).Frequency of the D allele carriers(ID+DD) was 55.61% in the CHD group and 52.29% in the control group.Compared with the II homozygote,no significant difference was found in the CHD risk of the carriers of D allele(ID+DD)(χ2=0.46,P=0.50,Or=0.87,95% CI=0.58～1.30).Subsequent stratified analysis revealed that the distribution of CX37 I1297D genotype and allele frequency in the myocardial infarction group was also similar to the control group(p>0.05). After adjustment for conventional risk factors,including gender,age,body mass index,smoking status,hypertension,diabetes mellitus and hypercholesterolemia,a binary logistic-regression analysis suggested that no difference was demonstrated between the I1297D polymorphism and CHD(p>0.05). Conclusions CX37 gene I1297D polymorphism is not associated with an increased risk of premature CHD in Chinese Han population and might not be considered as an independent predictor factor of the coronary atherosclerotic disease.