OBJECTIVE - Although metabolic syndrome is related to an increased risk of coronary heart disease (CHD) events, individuals with metabolic syndrome encompass a wide range of CHD risk levels. This study describes the distribution of 10-year CHD risk among U.S. adults with metabolic syndrome. RESEARCH DESIGN AND METHODS - Metabolic syndrome was defined by the modified National Cholesterol Education Program (NCEP)/Third Adult Treatment Panel (ATP 111) definition among 4,293 U.S. adults aged 20-79 years in the National Health and Nutrition Examination Survey 2003-2004. Low-, moderate-, moderately high-, and high-risk statuses were defined as <6, 6 to <10, 10-20, and >20% probability of CHD in 10 years (based on NCEP/ATP III Framingham risk score algorithms), respectively; those with diabetes or preexisting cardiovascular disease were assigned to high-risk status. RESULTS - The weighted prevalence of metabolic syndrome by NCEP criteria in our study was 29.0% overall (30.0% in men and 27.9% in women, P = 0.28): 38.5% (30.7% men and 46.9% women) were classified as low risk, 8.5% (7.9% men and 9.1% women) were classified as moderate risk, 15.8% (23.4% men and 7.6% women) were classified as moderately high risk, and 37.3% (38.0% men and 36.5% women) were classified as high risk. The proportion at high risk increased with age but was similar among Hispanics, non-Hispanic whites, and non-Hispanic blacks. CONCLUSIONS - Although many subjects with metabolic syndrome have a low calculated risk for CHD, about half have a moderately high or high risk, reinforcing the need for global risk assessment in individuals with metabolic syndrome to appropriately target intensity of treatment for underlying CHD risk factors.