Objectives: This study was performed to identify the socioeconomic factors, the psychosocial factors and the heath behavior factors that have an influence on abdominal obesity, as measured by using the waist circumference. Methods: Data was obtained from individuals aged above 20 years who had their waist circumference measured on the Korean National Health and Nutrition Examination Survey 2001, which was a cross-sectional health survey. Results: Regression analysis of the factors that affect abdominal obesity showed that the education level, income, smoking, duration of smoking, drinking consumption, frequency of exercises and sleeping were the associated factors for abdominal obesity. For men, the duration of smoking, education level, income and drinking consumption were the associated factors for abdominal obesity. For woman, the education level, income, duration of smoking, drinking consumption and frequency of exercise were the associated factors for abdominal obesity. Conclusions: Abdominal obesity is a risk factor for morbidity and mortality, and it is associated with chronic diseases, including cardiovascular disease and diabetes. Based on the findings, it is essential to modify heath behaviors for preventing abdominal obesity, which is a condition associated with the incidence of chronic disease.