Peripheral arterial disease (PAD) is a subclinical marker of coronary artery disease and identifies asymptomatic individuals at high risk for cardiovascular disease (CVD) events. The metabolic syndrome (MetS) is a constellation of clinical factors that increases the risk of developing diabetes and CVD. The authors' objectives were to estimate the prevalence of MetS in patients with PAD and to determine the prevalence of PAD in the population of asymptomatic US adults 40 years and older with MetS. The authors analyzed data from 3 National Health and Nutrition Examination Surveys (NHANES, 1999–2004). Prevalence of MetS as defined by the Third Report of the Adult Treatment Panel criteria and prevalence of associated cardiac risk factors were determined in 5376 asymptomatic participants 40 years and older. Presence of PAD was defined as ankle-brachial index <0.9. Estimates were weighted with the sample weights accounting for the unequal selection probability of complex NHANES sampling and over sampling of selected population subgroups. Prevalence of PAD in asymptomatic US adults 40 years and older was 4.2%. PAD prevalence in persons with MetS was 7.0% compared with 3.3% in persons without MetS. A total of 38% of the population with PAD also had MetS. High rates of abdominal obesity, hypertension, hyperglycemia, and low high-density lipoprotein cholesterol are significant contributors to both MetS and PAD. Persons with MetS have twice the risk of having PAD. Of persons with PAD, almost 40% have MetS. The presence of either PAD or MetS should warrant screening for both conditions so that risk stratification and management of risk factors may be performed.