To investigate the association between the connexin 37 (CX37) C1019T polymorphism and the susceptibility to coronary artery disease (CAD) in northern Han population of China. A total of 514 CAD patients and 400 healthy controls diagnosed by angiography were genotyped by using polymerase chain reaction-restriction fragment length polymorphism and polyacrylamide gel electrophoresis. The genotype frequencies of CC, TC and TT in the CX37 C1019T polymorphism was 22.37%, 53.31% and 24.32% in CAD patients, 17.75%, 46.50% and 35.75% in the controls respectively (P = 0.0007). The frequency of the CX37 C allele in CAD patients was significantly higher than that of the control group (49.03% vs 41.00%, OR = 1.38, 95% CI = 1.15 - 1.66, P = 0.0006). The frequency of the C allele carriers (CC + TC) was 75.68% in the CAD group and 64.25% in the control group (P = 0.0002). Compared with the TT homozygote, the CAD risk was significantly increased in the carriers of C allele (CC + TC) (OR = 1.73, 95% CI = 1.30 - 2.30). Subsequent stratified analysis revealed that the frequency of C allele was significantly higher in the male CAD patients than in the male controls (49.37% vs 39.60%, OR = 1.49, 95% CI = 1.18 - 1.89, P = 0.0009). The CAD risk was nearly two-fold increased in the carriers of C allele (CC + TC) than in the TT homozygote (95% CI = 1.38 - 2.78). However in the female population, there was no difference in the CAD risk between the carriers of (CC + TC) type and the TT homozygote (P = 0.24). The C allele in the CX37 gene might be associated with the susceptibility to CAD and potentially plays an important role in the manifestation of coronary atherosclerosis among Chinese.