Abstract: AIM: To investigate the morbidity and risk factors of contrast-induced nephropathy( CIN) in patients undergoing percutaneous coronary intervention( PCI) after conventional treatment,including risk assessment before PCI,optimal hydration before and after PCI and statin therapy. METHODS: One hundred and eighty-one consecutive patients who underwent hydration and PCI were enrolled. Serum creatinine was measured before and 72 h after PCI. RESULTS: The morbidity of CIN was 13. 8%. Multiple logistic regression analyses showed that CIN was associated with pre-contrast creatinine clearance,old age,lower hematocrit value and hypertension. CONCLUSION: The morbidity of CIN after conventional treatment is not noticeably lower than the average incidence reported in the literature. Pre-contrast creatinine clearance,old age,anemia and hypertension are independent risk factors for CIN.