Objective: To explore the association of-634C/G polymorphism of interleukin-6 (IL-6) gene with coronary artery disease(CAD). Methods: A total of 86 CAD patients and 91 healthy controls were selected for this study. The PCR-based restriction fragment length polymorphism (PCR-RFLP) technique was performed to assess the genotypes frequencies. The concentration of serum IL-6 was measured with ELISA. The relations of the levels of serum IL-6 between groups were analyzed. Results: The circulating IL-6 levels in the CAD group[(26.57 ± 6.68) ng/L] were significantly higher than those in the control group[(6.89 ± 2.32) ng/L,P < 0.05]. The distribution of the IL-6 -634C/G genotypes (CC,CG, and GG) was 65.9%,3 1.9% and 2.2% in the controls,and 57%, 29% and 14% in the CAD group, respectively(P < 0.05). Compared with the wild type CC,the G allele carriers(CG+GG genotypes) had higher circulating IL-6 levels[(34.575 ± 6.618)ng/L vs.(16.758 ± 5.182)ng/L, P < 0.05] in the CAD group. Conclusion:These findings suggest that IL-6 -634C/G polymorphism is associated with CAD and the G allele carriers have increased circulating IL-6 levels.