Growth patterns of eleven male subjects affected by congenital adrenal hyperplasia (CAH) due to 21 hydroxylase deficiency were studied and correlation with treatment was evaluated. All patients had completed their growth and were divided into two groups according to the age of diagnosis; group A: treated before 6 months of age (5 patients), group B: treated after 3 years of age (6 patients). Besides the pattern of growth, mean parental age, genetic target, onset and completion of puberty were considered. Regardless of the age at diagnosis, the patients of both groups had an anticipated and stunted final height vs. general population, but correlated with mean parental height. In all patients pubertal spurt failed and height velocity slowed down after twelve years of age. We conclude that pattern of growth of patients with CAH is deeply influenced by genetic and constitutional factors and by negative effects of glucocorticoid therapy. Actually an excellent glucocorticoid treatment of CAH is not available as yet and careful clinical and laboratory evaluations are necessary to minimize negative influences on growth.