Objective To investigate the relationship of the expression levels of serum miR-140 and miR-211 in elderly patients with coronary heart disease(CHD)and collateral circulation forma-tion.Methods A total of 151 CHD elderly patients undergoing surgical treatment in our hospital were included as the study subjects,and were divided into non-collateral circulation group(100 cases)and collateral circulation group(51 cases)according to the presence or absence of collateral circulation.RT-qPCR was applied to detect the expression levels of miR-140 and miR-211 in the serum.Results Larger proportions of culprit coronary artery＞3 branches and stenosis ≥75％and higher serum miR-211 level,but lower miR-140 level were observed in the non-collateral cir-culation group than the collateral circulation group(P＜0.01).The number of coronary artery lesions and the severity of coronary artery stenosis were negatively correlated with serum miR-140 level(r=-0.546,P＜0.01;r=-0.562,P＜0.01),and positively with miR-211 level(r=0.539,P＜0.01;r=0.528,P＜0.01).Multivariate logistic regression analysis indicated that miR-140 was a protective factor while miR-211 was an independent risk factor for collateral circulation formation in elderly CHD patients(P＜0.01).The area under the curve of the two indicators com-bined together in predicting collateral circulation formation was 0.896(95％CI:0.834-0.938,P＜0.05).Conclusion Serum miR-140 and miR-211 are both influencing factors for collateral cir-culation formation,and their combination has high predictive value for the formation.