Background Few studies have investigated the relationship between hyperuricemia and Contrast-induced nephropathy in patients with chronic kidney disease undergoing percutaneous coronary intervention.Methods A total of 446 consecutive patients with chronic kidney disease undergoing percutaneous coronary intervention were enrolled.Patients were divided into two groups according to serum uric acid (hyperuricemic group,n=205, and normouricemic group, n=241).We examined the occurrence of CIN and the major adverse cardiac events in hospital.The relationship between the incidence of CIN and hyperuricemic was evaluated by multivariate Logistic regression Analysis.HUA was defined as serum uric acid ＞420 tmol/L for male, ＞357 μmol/L for female.CIN was defined as ≥0.5 mg/d or ≥25％ increase from baseline Cr within 48-72 hours after contrast medium exposure.