OBJECTIVE: Race is a known risk factor for hypertension and cardiovascular disease in adults and influences blood pressure (BP) in children. We sought to determine if there are differences in clinical, laboratory, or echocardiographic characteristics among children with primary hypertension from different racial groups. PATIENTS AND METHODS: Study participants were 184 children aged 3 to 20 years with a diagnosis of primary hypertension who were examined at 1 of 3 participating centers at the time of initial evaluation of elevated BP. Black children were categorized as African American (AA) and nonblack children as non-AA. Comparisons were made for the entire group and after stratification according to age (<13 or ≥13 years). RESULTS: Overall, children categorized as AA had a higher prevalence of overweight/obesity and left ventricular hypertrophy and had higher plasma renin activity than children who were categorized as non-AA. After age stratification, these differences remained only in the children younger than 13 years old; there were no differences in these findings among children aged 13 years or older. AA children who were aged 13 years or older, however, had higher BPs for both casual and ambulatory measurements. Specifically, they had higher casual diastolic BP, higher 24-hour diastolic BP, higher daytime systolic and diastolic BP, and higher BP loads at night and over a 24-hour period compared with non-AA children who were aged 13 years or older. CONCLUSIONS: These data indicate that black children with primary hypertension may be at increased cardiovascular risk compared with nonblack children with primary hypertension. However, the high prevalence of overweight/obesity and left ventricular hypertrophy in all youth with primary hypertension demonstrates the need for greater preventive and therapeutic efforts aimed at reducing cardiovascular risk in this vulnerable population.