Purpose We estimated the prevalence of nocturia in the United States 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 20052006 and 20072008 cycles of the NHANES, a cross-sectional survey of the United States noninstitutionalized population. Getting up 2 or more times at night to urinate was coded as nocturia. Potential factors included age, race/ethnicity, education, waist circumference, self-reported health status, chronic diseases, and prior diagnosis of benign prostatic enlargement and/or prostate cancer (men 40 years old or older). Prevalence and prevalence odds ratios were estimated from a multivariable logistic regression analysis using appropriate sampling weights. Results The prevalence of nocturia was 21% (weighted 95% CI 19.323.0). Nocturia increased in prevalence with age (p <0.001) from 8.2% (CI 6.710.2) in men 20 to 34 years old up to 55.8% (CI 51.360.2) in men 75 years old or older. More nonHispanic black men had nocturia (30.2%, CI 26.734.1) than other racial/ethnic groups (20.1%, CI 18.122.1, p <0.001). Significant factors included 10-year increase in age (POR 1.5, CI 1.51.6), nonHispanic black race/ethnicity (POR 2.0, CI 1.62.7), fair/poor self-rated health (POR 1.5, CI 1.21.9), major depression (POR 2.5, CI 1.63.9), hypertension (POR 1.4, CI 1.01.9) and arthritis (POR 1.3, CI 1.01.7). Among men 40 years old or older benign prostatic enlargement (POR 1.4, CI 1.11.8) and prostate cancer (POR 1.6, CI 1.02.4) were associated with nocturia. Conclusions After adjusting for age and race norms nocturia was common among United States men. NonHispanic black men had greater odds of nocturia even when controlling for other factors. © 2011 American Urological Association Education and Research, Inc.