We investigated chronic effects of ethyl alcohol on adenohypophysis in adult Wistar rats and adenohypophysis in development including the postnatal period up to 30 days. Morphological findings in gonadotropic, prolactin and follicular cells were compared. After three months of constant alcohol consumption in the form of a 15% liquid solution, vacuolization of gonadotropic cells which acquire the shape of a seal ring, as well as nodular hyperplasia of chromophobe cells combined with sparse somatotropic cells, occur in the adenohypophysis of adult male rats. Electronic microscope revealed a small quantity of prolactin granules in light-microscopic chromophobe cells. In young rats exposed to alcohol gonadotropic and prolactin cells are unchanged but an accumulation of follicular cells within multiple smaller pseudofollicles is present. In the explanation of the differences between the findings obtained in adult and young rats with reference to LH/FSH and PRL cells, a stress is given to the role of the peripheral metabolism of testosterone and of hyperestrogenemia caused by alcohol consumption in adult rats lacking in young ones. The increased number of the follicular cells in adenohypophyses of young rats is likely to reflect the suppressed maturation of hypophyseal secretory cells.