Background and Objectives: It is still controversial whether carotid plaque is associated with major adverse cardiovascular events (MACE) especially in patients with coronary artery disease (CAD), although carotid intima-media thickness (CIMT) is well disclosed in the clinical meaning. Subjects and Methods: The study population, consists of 1473 consecutive patients with CAD, was followed up for a mean of 40.7 months (maximum 126 months). Fifty patients (3.4%) were excluded due to poor ultrasound image. We defined carotid plaque as focal structure encroaching into the arterial lumen of at least 0.5mm or 50% of the surrounding CIMT value or a thickness > 1.3mm as measured from the media-adventitia interface to the intima-lumen interface. Results: Patients with carotid plaque (n=449, 31.6%) were older (65.3 vs. 57.1 yrs, p<0.001), higher prevalence of hypertension (58.8% vs. 45.5%, p<0.001), diabetes mellitus (28.1% vs. 22.2%, p=0.016), old myocardial infarction (8.7% vs. 5.3%, p=0.017), acute coronary syndrome (33.9% vs. 24.4%, p<0.001), lower ejection fraction (63.5% vs. 65.1%, p<0.001), higher prevalence being treated with revascularization (44.5% vs. 35.8%, p=0.001), higher level of fasting blood sugar (132mg/dL vs. 121mg/dL, p<0.001), higher homocysteine (11.4mg/dL vs. 10.6mg/dL, p=0.009) and higher serum creatinine (1.08mg/dL vs. 0.90mg/dL, p=0.002) than those without carotid plaque (n=974, 68.4%). In univariate analysis, patients with carotid plaque had higher mortality (7.6% vs. 2.2%, p<0.001), restenosis (14.3% vs. 8.2%, p<0.001), target lesion revascularization (9.6% vs. 6.2%, p=0.021), hospitalization for congestive heart failure (3.8% vs. 1.4%, p=0.005) and total MACE (32.5% vs. 16.5%, p<0.001) than those without carotid plaque. Multivariate Cox regression analysis showed that the independent predictors of total MACE were carotid plaque (HR 1.388, 95% CI 1.085 to 1.777, p<0.009), CIMT (HR 1.400, 95% CI 1.099 to 1.784, p<0.006), old myocardial infarction (HR 2.218, 95% CI 1.575 to 3.124, p<0.000). Patients with carotid plaque had almost 7-times higher risk of cardiac death (HR 7.369, 95% CI 2.012 to 26.987, P=0.003) than those without carotid plaque. Conclusion: Carotid plaque is associated with 7-times higher risk of cardiac death, higher risk of restenosis and congestive heart failure in patients with CAD during more than 3-years follow up period, which suggest that carotid plaque has an important role in secondary prevention than CIMT.