Racial difference in ventilatory lung function were evaluated in a community study of 393 children (158 blacks, 235 whites). Mean forced vital capacity was 18% larger in nonsmoking white males than in nonsmoking black males and 11% larger in nonsmoking white females than in nonsmoking black females. Similar differences were observed for the 1 s forced expiratory volume and for the maximal expiratory flow at 50% of the forced vital capacity. When adjusted for lung size (on the basis of forced vital capacity) 1 s forced expiratory volume and maximal expiratory flow at 50% of the forced vital capacity were larger in the black children compared to the white children. Lung function prediction equations based on race, sex, age, height and weight are presented for healthy nonsmoking children; these allow for an evaluation of normal lung function in black and white children.