Objectives. The aim of this study was to evaluate the association between metabolic syndrome and periodontitis in Korean adult population. Methods. We analyzed a total of 2,808 subjects aged 18 years or older who participated in a Korea National Health and Nutrition Examination Survey in 2007. Periodontal health was measured using Community Periodontal Index (CPI). Periodontitis was defined as CPI score was three or four. Metabolic syndrome (MS) was the diagnosis when participants were positive for three or more of five components of MS. The association between periodontitis and MS was analyzed using a χ2-test and logistic regression analysis (using SPSS 17.0). Results. The prevalence of periodontitis was higher among people who were male, older, and current or ex-smokers. People having periodontitis were likely to have lower household incomes, and do more frequent toothbrushing and drinking. Persons having MS had significantly higher odds of having periodontitis than normal people; the odds ratio was 1.23 after adjusting for age, gender, education, intake of alcohol, smoking, toothbrushing, oral hygiene goods, eating between meals, exercise and household income (95% CI: 1.02~1.47). Conclusions. Korean adults with MS had a higher risk of periodontitis. Further studies are required to investigate a casual relationship between MS and periodontitis.