Aim To investigate the correlation between uric acid and circulating endothelial progenitor cell(EPC)in patients with coronary artery disease(CAD)and its clinical significance. Methods 78 cases were divided into 3 groups: stable angina pectoris(SAP)group(n=18),acute coronary syndrome(ACS)group(n=24)and control group(n=36),and CAD patients were divided into 3 groups according to the result of coronary angiography: single vessel disease group(n=18),double vessels disease group(n=14)and triple vessels disease group(n=10).The concentration of serum uric acid was measured with method of uric acid enzyme.Total mononuclear cell were isolated from peripheral blood by Ficoll density gradient centrifugation,and were cultured in M199 medium supplemented with 20% fetal bovine serum,50 μg/L vascular endothelial growth factor(VEGF).After 14 days cultured,the number of colony-forming units of EPC were counted by phase-contrast microscope. Results The uric acid level in the CAD group was significantly higher than those in control group(p<0.01),and there was no statistical difference between the uric acid level of single vessel disease group and that of multiple vessels disease groups(p<0.05).The number of colony-forming units of circulating EPC in CAD group(including SAP and ACS groups)was significantly lower than those in control group(p<0.01),and the circulating EPC level of single,double,triple vessels disease group were significantly lower than that of control group(p<0.01). It was also observed there was a strong negative correlation between the concentration of serum uric acid and the number of colony-forming units of circulating EPC(r=-0.382,P=0.037). Conclusions The serum uric acid concentration in CAD group was higher than that of control group,but the levels of uric acid were independent of the degree of coronary artery disease.The levels of circulating EPC of CAD patients were lower than those of healthy person.Uric acid and EPC were associated with CAD and the severity of coronary artery lesion,and the level of uric acid was negatively correlated with the number of colony-forming units of circulating EPC.These data indicate that uric acid may impair EPC-mediated reendothelialization after endothelial cell injury by inhibiting the number of the EPC,and uric acid and EPC are correlated with the degree of patient's condition and the clinical situation of cardiovascular disease.