Dehydroepiandrosterone and dehydroepiandrosterone-sulfate are precursors of androgens and estrogens, support the gonadal sexual steroid production. The levels of dehydroepiandrosterone and dehydroepiandrosterone-sulfate are maximal between the ages of 20 and 30 years, then start a decline of 2% per year, leaving a residual of 10-20% of the peak production by the eight decade of life. The age-associated decrease may lead to osteoporosis, deterioration of lipid-metabolism, cardiovascular diseases and second type of diabetes mellitus. Decreased levels were found in autoimmune diseases and in sexual dysfunction, too. Intracrinology describes the formation of active hormones which exert their action in the same cells where synthesis took place without release into the pericellular compartment. The high local androgen and estrogen concentration may be important in the pathomechanism of hirsutism, acne, seborrhea, breast and prostate cancer. Administration of dehydroepiandrosterone resulted in a reduction of postmenopausal osteoporosis, also the decreased symptoms in systemic lupus erythematosis, psychiatric diseases and sexual disfunction. The authors summarize the metabolism of dehydroepiandrosterone and dehydroepiandrosterone-sulfate and their role in different diseases.