Purpose: Carotid artery ultrasonography is a noninvasive and simple method for the assessment of intima-media thickness (IMT) of common carotid artery (CCA) and presence of carotid artery plaque. some studies have not shown the relationship between IMT of CCA and severity of CAD, also many contradictory reports for carotid artery plaque can predict the presence of CAD have been published. The aim of this study was to test the correlation between IMT of CCA and severity of CAD and the presence of carotid artery plaque can predict the CAD. Methods: All study subjects (n=158, age=63짹12) that underwent carotid artery ultrasonography and coronary angiography. Carotid artery ultrasonography was performed by using high-resolution with 7 MHz linear probe and the carotid IMT was semi-automatically measured. Results 1. Increased number of coronary artery disease vessel was closely related to the carotid artery maximal IMT (r=0.398, p<0.01, Spearman���s correlation test) and carotid artery mean IMT (r=0.419, p<0.01, Spearman���s correlation test). 2. The presence of carotid artery plaque to the number of disease vessel 3. In binary logistic regression analysis for predict the presence of CAD, Odds ratio for smoking was 2.9 (95% confidence interval 1.2-6.9) and Odds ratio for carotid artery plaque was 3.0 (95% confidence interval 1.3-7.0). Conclusions: Our data suggest that presence of carotid artery plaque on ultrasonography can predict CAD and also significant correlation between carotid artery IMT and severity of CAD.