A case of male pseudohermaphroditism with 47,XYY karyotype in blood and cutaneous fibroblasts is described. The plasma testosterone response to HCG stimulation was slightly below the normal range on two occasions suggesting a deficit of gonadal function. A study of the receptors for dihydrotestosterone in fibroblasts of genital and nongenital skin showed a normal concentration of receptors in genital skin; 5-alpha-reductase activity in fibroblasts of the genital skin was low, but the plasma relationship testosterone/dihydrotestosterone under HCG stimulation was normal. The diagnostic possibility of a complete testicular feminization syndrome with normal receptors for dihydrotestosterone is commented on.