This study identified factors associated with unhealthy lifestyle behaviors in people with metabolic syndrome in South Korea. The sample consisted of 1,207 subjects with metabolic syndrome from the Sixth Korea National Health and Nutrition Examination Survey conducted in 2014. High-risk alcohol consumption, smoking, aerobic physical activity, leisure physical activity, excessive carbohydrate intake, and fat intake were measured. A secondary data analysis was performed using chi-square tests and logistic regression. Gender was associated with all unhealthy behaviors. The number of metabolic syndrome components, a poor perceived health status, and attempts to control weight were associated with physical inactivity. Those findings may be helpful to develop a tailored lifestyle modification programs for people with metabolic syndrome.