Patients with systemic lupus erythematosus (SLE), systemic scleroderma (SSD) and donors were examined for the blood levels of adrenocorticotropic hormone, hydrocortisone, follicle-stimulating hormone, luteinizing hormone, prolactin, estradiol, testosterone, progesterone, thyroid-stimulating hormone, triiodothyronine, thyroxin, and insulin. The corticotropin load test was carried out in 38 SLE patients, 32 SSD patients and 24 donors. The prednisolone test was made in 15 SSD patients and 27 donors. The studies were made with the aid of RIA. The patients with SLE manifested a decline of the basal level of hydrocortisone as well as a reduction of the reserve potentialities of the pituitary-adrenal system. The patients with SSD demonstrated a negligible decrease of the basal level of hydrocortisone with an evident lowering of the reserves of the same system. The treatment of SLE and SSD patients with glucocorticoids was followed by marked hyperinsulinemia.