Purpose: We estimated the prevalence of urinary incontinence in the United States adult male population and identified associated factors. Materials and Methods: Data were analyzed for 5,297 men 20 years old or older who participated in the 2005 to 2006 and 2007 to 2008 cycles of the National Health and Nutrition Examination Survey, a cross-sectional, nationally representative survey of the United States noninstitutionalized population. Urinary incontinence (score of 3 or greater on a validated incontinence severity index, indicating moderate to severe leakage) was assessed. Potential associated factors included age, race/ethnicity, education, self-reported health status, prior diagnosis of prostate cancer and/or enlarged prostate (men 40 years old or older), chronic diseases and depression status. Prevalence ORs were estimated from a multivariable logistic regression analysis using appropriate sampling weights. Results: The prevalence of moderate/severe urinary incontinence was 4.5% (95% CI 3.8, 5.4). Prevalence increased with age from 0.7% (95% CI 0.4, 1.6) in men 20 to 34 years old, to 16.0% (95% CI 13.0, 19.4) in men 75 years old or older (p <0.001). We found no difference in prevalence by racial/ethnic group (p = 0.38). Factors significantly associated (p <0.05) with urinary incontinence were age (per 10-year increase, OR 1.8; 95% CI 1.6, 2.0), major depression (OR 2.7; 95% CI 1.6, 4.0) and hypertension (OR 1.3; 95% CI 1.1, 1.5). Conclusions: Age and race adjusted prevalence estimates for urinary incontinence in men are consistent with other estimates using a similar definition. To our knowledge this is the first study that identifies factors associated with moderate to severe urinary incontinence in men. © 2010 American Urological Association Education and Research, Inc.