Background and purpose: Coronary artery bypass surgery (CABG) is an effective and important treatment for patients with coronary artery disease. In recent years there has been increasing interest in prediction of mortality and patient's outcome after cardiac surgery. Several models have been designed to identify related risk factors. This study aimed at evaluating EuroSCORE model in CABG patients in Sari Fatemeh Zahra Center for Cardiac Surgery. Materials and methods: A cross-sectional study was performed and EuroSCORE was calculated for 1000 patients who had CABG. To determine the rate of mortality, the patients were followed for 30 days after the surgery. The main risk factors affecting mortality and validity and reliability of EuroSCORE were also evaluated. Results: Thirty-day mortality rate was 1.5%. The main risk factors affecting mortality rate were age, poor left ventricular dysfunction, chronic pulmonary disease, high serum Cr, critical preoperative state, pulmonary hypertension, other than CABG and post infarct septal rupture. Conclusion: EuroSCORE model could predict the rate of mortality in 78% of the samples. In other studies this rate was predicted at 75%, therefore, EuroSCORE model was found more efficient in this study.