We assessed the influence of insulin resistance (IR) on the development of contrast-induced nephropathy (CIN) in patients (n = 719) undergoing elective percutaneous coronary intervention (PCI). Patients were divided into diabetes mellitus (DM = 242), nondiabetic IR (IR = 120), and nondiabetic insulin sensitivity (IS = 357) groups according to medical history and homeostasis model assessment insulin resistance index. Serum creatinine (SCr) and estimated glomerular filtration rate (eGFR) were measured before and 72 hours after PCI. There were no differences in SCr and eGFR among the groups before PCI; SCr increased and eGFR decreased significantly in the DM and IR groups post-PCI (P < .001). The incidence of CIN in the IR group was as high as in the DM group and were both significantly higher than in the IS group (6.7% vs 8.7% vs 2.2%, P < .05). Multivariate logistic regression analysis showed DM (odds ratio [OR] = 1.19, 95%CI = 1.08-1.510, P < .001), HOMA-IR (OR = 1.39, 95%CI = 1.23-1.58, P < 0.001), and eGFR (OR = 0.88, 95%CI = 0.84-0.92, P < .001) were independent risk factors in predicting CIN. Screening IR patients and taking appropriate prophylactic strategy before PCI may reduce the incidence of CIN.