The excretory patterns of urinary steroids determined by capillary gas chromatography in 11 children (aged 0.8-16.5 years) with adrenocortical tumors were established. In 8 patients the predominant clinical feature was virilization, in 3 others, Cushing's syndrome. In 5 patients (3 carcinoma, 2 adenoma) very high excretion of 3 beta-hydroxy-5-ene steroids was observed. In 2 others (adenomas) only moderately elevated excretion of 11 beta-hydroxyandrosterone was found. In 1 patient (adenoma) pregnanediol dominated in the steroid profile, accompanied by moderately elevated 3 beta-hydroxy-5-ene steroids. Out of 3 Cushingoid patients (1 carcinoma, 2 adenomas), 1 presented an atypical urinary steroid pattern for hypercortisolemia, without 5 alpha-reductase and 11 beta-hydroxysteroid dehydrogenase deficiencies. Neither the urinary steroid pattern nor tumor size alone were reliable indicators of tumor malignancy, as evaluated by a pathological examination and subsequent metastasis-free survival.