PURPOSE: Obesity is related to many diseases, including urological conditions. We investigated the prevalence, risk factors, and treatment of male obesity. MATERIALS AND METHODS: This study included 17,485 men older than 20 years of age who participated in the fourth, fifth, and sixth administrations of the Korean National Health and Nutrition Examination Survey. Two main cutoff points for obesity were defined: a body mass index (BMI) ≥25 kg/m2 and a BMI≥30 kg/m2. Additionally, we defined obesity requiring pharmacotherapy as the presence of a BMI≥30 kg/m2 or a BMI≥27 kg/m2 co-occurring with at least one associated comorbid medical condition, such as hypertension, dyslipidemia, or diabetes. RESULTS: The prevalence rates of a BMI≥25 kg/m2, a BMI≥30 kg/m2, and obesity requiring pharmacotherapy were 35.7%, 3.4%, and 10.5%, respectively. The prevalence of obesity increased over time for all definitions of obesity. The prevalence of obesity requiring pharmacotherapy was highest in Jeju (12.5%) and lowest in Gangwon-do (7.7%). Having a higher income, being a non-manual worker, and having completed a high level of education were significantly related to obesity requiring pharmacotherapy. More than 70% of patients with obesity requiring pharmacotherapy reported taking diet pills, eating functional foods, or consuming a one-food diet for weight reduction, but only 13.9% reported exercising for this purpose. CONCLUSIONS: Male obesity is a common condition, the prevalence of which is expected to continue to increase over time. A better strategy is required to manage male obesity in Korea.