The objective of this study was to determine the contribution of regional fat localizations defined as abdominal (AO) or truncal (TO) obesity in racial/ethnic differences to the prevalence odds of hypertension in overweight American adults. Data (n ¼ 5694) from the 1999-2002 US National Health and Nutrition Examination Survey were utilized for this analysis. Abdominal obesity was defined as waist circumference X102 and X88 cm for men and women, respectively. Truncal obesity was defined using ratio of subscapular to triceps skinfold thickness and were X2.24 and X1.32, for men and women, respectively. Prevalence odds ratios from gender-specific logistic regression models were used to evaluate the contribution of regional fat localizations to racial/ethnic variation in hypertension. Statistical adjustment was made for age, education, alcohol intake and body mass index. In both men and women, coexistence of AO and TO was associated with much higher prevalence odds of hypertension than association due to each of the regional fat localizations. In men, coexistence of AO and TO was associated with 1.99, 2.47 and 2.10 increased prevalence odds of hypertension in Whites, Blacks and Mexican Americans, respectively. The corresponding values in women were 2.83, 4.07 and 3.61 in Whites, Blacks and Mexican Americans, respectively. The coexistence of AO and TO appears to be the culprit that contributes to high blood pressure on top of body mass index. Weight reduction programs that are targeted toward abdominal and truncal regions in at-risk populations and along racial/ethnic lines may help to alleviate racial/ethnic disparity in risk of hypertension.