1. Objectives The risk for cardiovascular diseases increases significantly when multiple risk factors exist, as in the form of metabolic syndrome, compared to a single risk factor. This study was to assess the prevalence rate of metabolic syndrome and evaluate the factors associated with metabolic syndrome and Sasang Constitutional Types. 2. Methods 666 subjects(280 men and 386 women), more 40 years old, in a rural community study were examined in point of Sasang Constitution and metabolic syndrome. 3. Results 1) Their Constitutional distribution were Taeeumin 436 persons (65.5%), Soyangin 83 persons (12.5%), Soeumin 147 persons (22.1%) and no Taeyangin diagnosed by PSSC. 2) Body weight, BMI, waist circumstance and hip circumstance were significantly high in Taeeumin group like previous study results. 3) Prevalence rate of metabolic syndrome was 32.0%, especially 27.1% in men and significantly higher as 35.5% in women than men. 4) In men, prevalence rate of metabolic syndrome was 1.4% in Soyangin, 2.9% in Soeumin and significantly high as 22.9% in Taeeumin. 5) In women, prevalence rate of metabolic syndrome was 12.5% in Soyangin, 3.6% in Soeumin and significantly high as 47.6% in Taeeumin. 6) Hazard ratios for metabolic syndrome were 1.14 for women to men, 2.34 for those at the age of 60s to 40s, 1.95 for Soyangin to Soeumin and 3.39 for Taeeumin to Soeumin. 4. Conclusions Sasang Constitutional Type may be an significant risk factor for metabolic syndrome and regimen according to Sasang Constitutional Type is thought to be needed to prevent metabolic syndrome.