Objective To assess the performance of the European System for Cardiac Operative Risk Evaluation Ⅱ(EuroSCORE Ⅱ) in predicating in-hospital mortality among Chinese patients undergoing heart valve surgery at our center. Methods From January 2006 to December 2011, 3 479 consecutive patients who underwent heart valve surgery at our center were enrolled in this study and they were scored by the original EuroSCORE(addtive EuroSCORE and logistic EuroSCORE) and EuroSCORE Ⅱ model. The actual mortality rate of patients was compared with those of the predicted ones. The performances of the original EuroSCORE and EuroSCORE Ⅱ model were assessed by the Hosmer-Lemeshow (H-L) test. The discrimination validity of prediction was tested by calculating the area under the receiver operating characteristic (ROC) curve. Results There were 112 in-hospital deaths among the 3 479 patients, with an in-hospital mortality rate of 3.2%, compared to the predicted mortality rates of 3.84% by the additive EuroSCORE (H-L: P=0.013, suggesting a higher prediction) ,3.33% by the logistic EuroSCORE (H-L: P=0.08, suggesting good consistency), and 2.52% by the EuroSCORE Ⅱ (H-L: P<0.0001, suggesting a lower prediction).EuroSCORE Ⅱ showed a good calibration in predicting in-hospital mortality for patients undergoing single valve surgery (H-L: P=0.103, area under the ROC curve of 0.792) and a poor calibration for patients undergoing multiple valve surgery (H-L: P<0.0001, area under the ROC curve of 0.605). The discriminative powers of the predictions by additive EuroSCORE, logistic EuroSCORE, and EuroSCORE Ⅱ were poor for the entire cohort, with the areas under the ROC curve being 0.684, 0.673, and 0.685, respectively.Conclusion EuroSCORE Ⅱ has a better accuracy for predicting mortality of patients undergoing single valve surgery, but not for those undergoing multiple valve surgery, which should be considered in clinical practice.