Introduction: Ischemic heart disease is the most common cause of mortality in developed countries. CABG (Coronary Artery Bypass Graft) is one of the therapeutic methods in ischemic heart disease. Methods and Materials: Considering the increased incidence of coronary artery disease in Iran, and with increased rate of CABG, we performed a cross sectioned study (1996-1999). In 635 patients 467 male (73.5 percent), 168 female (26.5 percent) about risk factors of mortality after CABG in cardiac surgery department "Imam Khomeini hospital. 20 risk factors were included in our study: age, gender, smoking, family history, diabetes mellitus, morbid obesity, hypercholesterolemia, hypertension, palpitation, renal failure COPD, (chronic obstructive pulmonary disease), history of myocardial infarction, CHF, angina, cerebral vascular disease, pace maker, Ejection fraction<40 percent, history of PTCA, history of CPR, and coronary endarterectomy. Results: Cigarette smoking (P=0.40), CHF in female (P=0.003). Endarterectomy in both gender (P=0.0001). Pace maker in both gender (P=0.00006), palpitation in both gender (P=0.0001). CPR in both gender (P=0.0000001), were associated with increased risk of mortality after CABG. Conclusion: We found that, endarterctomy, cigarette smoking, CHF. Pace maker, CPR, and palpitation are important risk factors for mortality after CABG.