ObjectiveTo assess the accuracy of European System for Cardiac Operative Risk Evaluation (EuroSCORE) model in predicting the in-hospital mortality of Uyghur patients and Han nationality patients undergoing heart valve surgery. MethodsClinical data of 361 consecutive patients who underwent heart valve surgery at our center from September 2012 to December 2013 were collected, including 209 Uyghur patients and 152 Han nationality patients. According to the score for additive and logistic EuroSCORE models, the patients were divided into 3 subgroups including a low risk subgroup, a moderate risk subgroup, and a high risk subgroup. The actual and predicted mortality of each risk subgroup were studied and compared. Calibration of the EuroSCORE model was assessed by the test of goodness of fit, discrimination was tested by calculating the area under the receiver operating characteristic (ROC) curve. ResultsThe actual mortality was 8.03% for overall patients, 6.70% for Uyghur patients,and 9.87% for Han nationality patients. The predicted mortality by additive EuroSCORE and logistic EuroSCORE for Uyghur patients were 4.03% and 3.37%,for Han nationality patients were 4.43% and 3.77%, significantly lower than actual mortality (P<0.01). The area under the ROC curve of additive EuroSCORE and logistic EuroSCORE for overall patients were 0.606 and 0.598, for Han nationality patients were 0.574 and 0.553,and for Uyghur patients were 0.609 and 0.610. ConclusionThe additive and logistic EuroSCORE are unable to predict the in-hospital mortality accurately for Uyghur and Han nationality patients undergoing heart valve surgery. Clinical use of these model should be considered cautiously.