Background: There has been a lot of controversy over the strategy for treating patient with severe carotid artery disease and coronary artery disease. For preventing stroke and other neurologic complications in patient who planned to undergo coronary artery bypass graft (CABG), carotid artery stenting (CAS) has been widely used as an alternative treatment for carotid endarterectomy (CEA). Limited data are available for the comparison of clinical outcomes between CEA and CAS in patients with significant carotid artery stenosis.Methods: From February 2003 to May 2009, 20 patients underwent CEA and CABG and 31 patients underwent CAS followed by CABG. All patients had severe (>80%) stenosis of carotid artery or moderate (>50%) stenosis with neurologic symptoms. We analyzed clinical outcomes of CEA and CAS after CABG. Death, stroke, myocardial infarction, and major adverse cardiac and cerebrovascular event were assessed at different times.Results: There was no difference of baseline clinical parameters between two groups. The incidence of combined death or stroke was 30.0% (n=6) in CEA group and 9.7% (n=3) in CAS group. The cumulative overall survival rates were not different in both group (68.8% vs. 88.3%, P=0.225). The cumulative stroke-free survival rates were significantly different between CEA and CAS group (48.1% vs. 88.3%, P=0.046). Two patients (10.0%) developed stroke after CEA compared with no stroke in patients who underwent CAS. Myocardial infarction was occurred in 1 patient of CEA group and target vessel revascularization was not occurred. Conclusion: In this study of patients with severe carotid artery stenosis, the rate of death and stroke were superior in CAS group compared with CEA group.