The period of transitory postnatal activation of the hypotalamo-pitutary-gonadal axis (mini-puberty) plays an important role in the testicular maturation and the development of the reproductive system. The objective of the present study was to evaluate the functional condition of the testicles in the boys at the age of 2-3 months born with cryptorchism. A total of 32 boys presenting with inguinal retention of the testes (group 1), 10 patients with unilateral abdominal criptorchism (group 2), and 40 healthy boys ages 2-3 month (control group) were available for the clinical examination and hormonal analysis. The methods employed in the study included orchidometry and genitometry, meagurement of serum gonadotropin, testosterone, and inhibin B levels by immunoenzyme assays. The results investigations made it possible to diagnose gonadal pathology in 80% of the examinad children presenting with unilateral abdominal cryptorchism and subclinical disorders of the testicular function in 40% of the patients with inguinal retention of a testicle.