1. Objectives The purpose of this study was to investigate the correlation of Metabolic syndrome(MetS) and Intima-media thickness(IMT) of common carotid artery with Sasang constitution. 2. Methods 197 subjects who had taken health examinations and diagnosis of Sasang constitution from Jan 1, 2006 to Dec 31, 2006 at East-west health examination center of Kyung-Hee medical center were included and underwent B-mode ultrasonography for measurement of intima-media thickness of common carotid arteries. MetS was defined by the criteria of the criteria of the National Cholesterol Education Program Adult Treatment Panel III. 3. Results and Conclusions Mean intima-media thickness of common carotid artery was significantly higher in subjects with MetS compared with control subjects($0.070{pm}0.017$ vs $0.063{pm}0.014cm$) and a significant trend towards increased IMT was observed with increasing numbers of metabolic syndrome components(r=0.331, p=0.000). After adjustment for age and sex, IMT of common carotid arteries was significantly different among three constitutional groups (Soyangin:$0.065{pm}0.015cm$, Taeumin:$0.068{pm}0.016cm$, Soeumin:$0.056{pm}0.010cm$), however, after adjustment for age, sex and existence of metabolic syndrome, there was no significant different. But, factor of Taeumin was the effective determinant of the increase of mean IMT of common carotid arteries.