Objective To investigate the safety of drug-coated balloon (DCB) in the treatment of coronary artery restenosis in elderly patients and its effects on the intimal response of target vessels and the revascularization of target lesions (TLR).Methods A total of 198 elderly patients with coronary artery restenosis in our hospital from November 2017 to January 2019 were enrolled and randomly divided into study group and control group, with 99 cases in each group. The control group was treated with the cutting balloon and the study group was treated with DCB. The intimal response of the target blood vessels [minimum lumen diameter of main branch (MLD) and minimum lumen area (MLA)], cardiac function [left ventricular ejection fraction (LVEF), N-terminal pro-brain natriuretic peptide (NT-proBNP) and stroke volume (SV)], Chinese questionnaire of quality of life in patients with cardiovascular diseases (CCQQ) score, the incidence of adverse cardiovascular events, and the rates of restenosis and TLR were measured before the treatment and 3 and 6 months after the treatment in two groups.Results MLD and MLA were different between the study group and the control group (P < 0.05), and LVEF, NT-proBNP, and SV were also different between the two groups (P < 0.05). There was no significant difference in the incidence of adverse cardiovascular events between the study group and the control group (P > 0.05). Besides, the incidence of TLR and CCQQ scores differed between the two groups (P < 0.05).Conclusions DCB treatment can significantly improve the intimal response of the target blood vessels, reduce the incidence of TLR, promote cardiac function recovery, and enhance quality of life in elderly patients with coronary artery restenosis.