OBJECTIVE： To evaluate the effects of angiotensin-converting enzyme inhibitor（ACEI）on the contrast-induced nephropathy （CIN） after percutaneous coronary intervention （PCI）. METHODS： 421 patients underwent PCI were retrospectively collected from our hospital during 2013-2014. Those patients were divided into trial group （193 cases） and control group （228 cases） according to the use of ACEI within 72 h before surgery. Trial group was given perindopril 4 mg orally， qd， or benazepril hydrochloride 10 mg， qd， within 72 h before surgery； control group was not given ACEI before surgery. The changes of serum creatinine （Scr）， blood urea nitrogen （BUN） and estimation of glomerular filtration rate （eGFR） were observed in 2 groups， and influential factor of CIN was analyzed by using duality logistics. RESULTS： Before surgery， there was no statistical significance in Scr， BUN and eGFR between 2 groups （P＞0.05）. After operation， Scr and BUN of trial group was increased significantly and higher than those of control group， while eGFR of trial group was decreased significantly and lower than that of control group， with statistical significance （P＜0.05）. The incidence of CIN in trial group was significantly higher than in control group （11.9％ vs. 4.4％）， with statistical significance （P＜0.05）. The independent risk factors of CIN included age， diabetes mellitus， hypertension， heart failure， renal disease， radiography dose， the use of ACEI before surgery （P＜0.05）. CONCLUSIONS： The use of ACEI in percutaneous coronary radiography would be harmful to the renal function and would increase the incidence of CIN.