In order to determine normal values for systolic blood pressure response to cycle ergometer stress testing in children, we performed 405 studies in subjects from 6 to 15 years of age, of whom 184 were black and 221 were white. We analyzed the data in relation to sex, color, age, and body surface area. Resting systolic blood pressure showed no differences between groups of black and white children, analyzed either by age or surface area. Peak exercise blood pressures were higher in the black females, in comparison to their white counterparts, only when separated into groups by body surface area. The black males had higher exercise blood pressure values than the whites, both by age and surface area evaluation. Our data suggest a difference in the blood pressure response to dynamic exercise within the black population. Further studies are needed to define the mechanism of this difference and whether this difference may provide a clue to the identification of children at increased risk for developing hypertension later in life.