Background and Purpose:The combination of cardiovascular risk factors known as the metabolic syndrome(MS) is receiving increased attention from physicians, but data on the syndrome���s association with morbidity and mortality are limited in known coronary artery disease(CAD) patients(pts) in Korea. Methods: We have prospectively enrolled 1665 consecutive pts with CAD who have admitted to 8 Catholic University Hospitals located in 6 different cities in Korea from December, 1999 to April, 2003. By applying National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) criteria, the MS was defined as at least 3 of the 5 conditions. Correlation between MS and cardiac events was analysed. Result: Of 1665, 1113 pts(M:F = 779:485) had complete data on all variables used in the analyses. 580(52.1 %) pts (M:F =289, 41.5%:291, 69.8%) had MS. There was no significant difference in incidence of cardiac events(death, myocardial infarction, target lesion revascularization, angina) between CAD pts with MS and CAD pts without MS. Conclusions: MS is more prevalent in female CAD pts (p<0.05). MS is less important in secondary prevention of CAD.