Abstract： Objective To validate the value of Cleveland Clinical Score to predict acute renal failure（ARF） requiring renal replacement therapy （RRT） and in-hospital death in Chinese adult patients after cardiac surgery. Methods A retrospective analysis was conducted for all the patients who underwent cardiac surgery from January 2005 to December 2009 in Renji Hospital of School of Medicine, Shanghai Jiaotong University. A total of 2 153 adult patients, 1 267 males and 886 females，were included. Their age ranged from 18 to 99 years with an average age of 58.70 years. Cleveland Clinical Score was used to predict ARF after cardiac surgery. ARF was defined as the need for RRT. Based on Cleveland Clinical Score, the patients were divided into four risk categories of increasing severity：0 to 2 point（n=979）, 3 to 5 point （n=1 116）, 6 to 8 point（n=54）, 9 to 13 point（n=4）. The rates of ARF, multiple organ system failure （MOSF）, and mortality were compared among the 4 categories. The predictive accuracy of postoperative ARF and hospital mortality was assessed by area under the receiver operating characteristic curve （AUC-ROC）. Results In the four categories, the rate of postoperative ARF was 0.92%, 1.88%, 12.96%, and 25.00%, respectively； MOSF rate was 1.23%, 1.88%, 3.70%, and 25.00%, respectively; mortality was 0.92%, 4.21%, 25.93%, and 50.00%, respectively. There was significant dif ference among the four categories in ARF rate （χ2=55.635, P=0.000），MOSF rate（χ2=16.080, P=0.001）, and mortality （χ2=71.470, P=0.000）. The AUC-ROC for Cleveland Clinical Score predicting ARF rate and hospital mortality was 0.775 （95%CI 0.713 to 0.837, P=0.000）and 0.764（95%CI, 0.711 to 0.817, P=0.000）, respectively. Conclusion Cleveland Clinical Score can accurately predict postoperative ARF and hospital mortality in a large, unselected Chinese cohort of adult patients after cardiac surgery. It can be used to provide evidence for effective preventive measures for patients at high risk of postoperative ARF.