Objectives: The aim of this study was to confirm the association among the health status, health behaviors, and periodontitis according to total, age and sex in cases of adult metabolic syndrome(MetS). Methods: This cross-sectional study used collected data from the 7th Korea National Health and Nutrition Examination Survey (KNHANES) conducted from 2016 to 2018 with 3,394 adults with MetS aged 19-79 years. The complex samples logistic regression analysis confirmed the relevant factors for periodontitis. Results:Periodontitis was diagnosed in 43.6% of all MetS cases. Diabetes (Odds Ratio [OR]=1.554), abdominal obesity (OR=1.336), current smoking (OR=2.465), past smoking (OR=1.379), and not-using oral care products (OR=1.414) were associated with periodontitis in MetS. In the age of 19-39 years with MetS group, diabetes (OR=5.379), elevated blood pressure (OR=3.975), current smoking (OR=7.430), and not using oral care products (OR=3.356) were associated with periodontitis. In the 40-79 age group, diabetes (OR=1.398), abdominal obesity (OR=1.360), current smoking (OR=2.022), and not using oral care products (OR=1.416) were associated with periodontitis. In the male MetS group, current smoking (OR=3.119), past smoking (OR=1.625), and brushing teeth more than three times (OR=0.743) were associated with periodontitis. In the female MetS group, diabetes (OR=1.733), impaired fasting glucose (OR=1.434), abdominal obesity (OR=1.479), and not using oral care products (OR=1.992) were associated with periodontitis. Conclusions: Improvement in blood sugar control, obesity, smoking cessation, and oral health education, including how to use oral care products in all individuals with MetS may result in improved oral health. In addition, improvement in elevated blood pressure in the MetS group aged under 40 years, and brushing teeth more than three times a day in the male MetS group can reduce the risk of periodontitis. Therefore, public and oral health professionals should emphasize on the relationship between age and sex during the metabolic syndrome management program and share relevant information with patients.