Background and Objectives : Metabolic syndrome and High sensitivity C-reactive protein(hs-CRP) have been known to be strong predictors of coronary atherosclerosis. Even though there are many observations and research results concerning the association of coronary atherosclerosis with CRP and metabolic syndrome, there are still problems to be solved in order to produce clear mechanistic illustrations. We intended to observe the correlations of Metabolic syndrome, hs-CRP and the severity of coronary atherosclerosis. Subjects and Methods : We observed 271 patients aged 29 to 87 years who underwent diagnostic coronary angiograms at National Medical Center from January, 2004 through June, 2006. Coronary angiograms were done in patients who complained of typical chest pain and had risks of coronary atherosclerosis. The correlations of Metabolic syndrome, hs-CRP and coronary atherosclerosis were analyzed in these patients. Results : There were positive relations among Metabolic syndrome, hs-CRP and coronary atherosclerosis. The severity of Coronary atherosclerosis increased as hs-CRP increased(p<0.01, Spearman's correlation). hs-CRP increased as Metabolic syndrome risk factors increased(p<0.01, Spearman's correlation). The 1, 2, 3 vessel disease increased 1.61, 1.83, 2.50 times, respectively, as Metabolic syndrome score increased(p=0.001, p<0.001, p<0.001, Multinomial logistic regression analyses). We could know that the severity of coronary atherosclerosis was associated with Metabolic syndrome and hs-CRP. Conclusion : The more Metabolic syndrome risk factors clustered, the more hs-CRP level and the severity of coronary atherosclerosis increased. hs-CRP might be not only the inflammatory biomarker but also the mediator and cause of inflammation.