Urinary preganediol has been estimated by the method of Klopper and associates in 85 children without any known metabolic or endocrine disorders. The values observed were in good agreement with those found by Klopper et al. in adult men and postmenopausal women. The average pregnanediol excretion in boys was 0.75 mg, and that in girls 0.72 mg/24 hours. For 3 girls in the premenstrual period, the values were higher. No correlation between pregnanediol excretion and the age of the children could be demonstrated. In 14 children with various endocrine disorders, values for pregnanediol excretion were essentially normal. Six children with congenital adrenal hyperplasia were also studied. The high values for urinary pregnanediol before treatment were distinctly reduced during cortisone therapy.