The present study examined the relationship between blood pressure and cognitive performance in 2727 healthy men and women between the ages of 20 and 59 years who participated in the Third National Health and Nutrition Examination Survey (NHANES III). Participants were selected from a subsample of 5662 NHANES III respondents who completed an initial home interview, a medical examination, and a series of computerized cognitive tests of visuomotor reaction time, complex psychomotor speed (ie, symbol digit substitution), and verbal learning/attention (ie, serial digit learning). Hierarchical regressions tested the contribution of resting blood pressure to the prediction of performance on each of the cognitive tests. Results indicated that, after controlling for demographic variables (age, sex, race/ethnicity, education) and resting blood pressure, the interaction of systolic blood pressure by age was a significant predictor of performance on the test of verbal learning/attention. Follow-up analyses revealed that higher systolic blood pressure was associated with poorer performance in those younger than 40 years. Expanding on findings from previous epidemiological studies, the present study reports a small but significant relationship between resting blood pressure and cognitive performance that is particularly evident in younger healthy adults.