Metabolic syndrome is a major risk factor for cardiovascular disease. Clustering of a combination of individual factors that increase the actual rather than the expected prevalence might be helpful in understanding the pathophysiology of metabolic syndrome. The aim of this study was to analyze the most influential factors for metabolic syndrome to assess clustering factors of metabolic syndrome.Subjects from the Korea National Health and Nutrition Examination Survey (KNHANES) VI were included in the present study. The status of health behaviors was obtained using the questionnaires included in the KNHANES VI. A complex, stratified, and multistage sampling design was used to analyze the data according to statistics from the Korea Centers for Disease Control and Prevention.A total of 2,101 men and 2,831 women aged older than 20 years were included in this study. In men, drinking alcohol more than twice per week was related with the prevalence of metabolic syndrome; while, in women, exercise was related with the prevalence of metabolic syndrome. The clustering effect was observed for more than three metabolic factors. In men, the clustering effect was strongest for the combination of hypertension, hyperglycemia, and hypertriglyceridemia. In women, the strongest clustering effect was observed for the combination of abdominal obesity, hypertriglyceridemia, and low high-density lipoprotein cholesterol concentration.The health behaviors affecting metabolic syndrome in men and women included drinking alcohol more than twice a week and exercising more than four times a week, respectively; in addition, hypertriglyceridemia most significantly influenced the clustering effect of metabolic syndrome.