OBJECTIVES: Metabolic syndrome components, insulin resistance and central obesity cause type 2 diabetes and hypertension. This will increase the risk of cardiovascular disease. Women after menopause are at increased risk of metabolic syndrome. Several researchers studied that in menopause, metabolic syndrome increased cardiovascular mortality. We studied the impact on cardiovascular mortality of postmenopausal women with metabolic syndrome in the Republic of Korea. METHODS: Twenty four thousand nine hundred forty nine postmenopausal women aged 40 years or older were enrolled at health promotion centers of national university hospital located in 18 regions during 1994-2004. Age, weights, height, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG), cholesterol, triglyceride (TG), high-density lipoprotein were evaluated and history taking about alcohol consumption, smoking, and exercise was performed. In addition, subjects who died of cardiac disease were analyzed from January 1995 to December 2009. RESULTS: Metabolic syndrome was higher in postmenopausal women with increased in age, BMI, blood pressure (BP), FBG, cholesterol, TG. Thirty cardiac deaths occurred during the observation period. Factors affecting cardiac death were age, smoking, FBG and when age and smoking were controlled. FBG was an important factor affecting cardiovascular mortality in our study. When controlling age, smoking, and alcohol consumption, metabolic syndrome caused an increased relative risk of cardiovascular mortality. Survival rate was much lower in postmenopausal women with metabolic syndrome than those without metabolic syndrome. CONCLUSION: Metabolic syndrome in Korean postmenopausal women increased cardiovascular mortality.