Percutaneous absorption of ³H-labelled beclomethasone dipropionate cream under plastic film was studied by means of an autoradiography. It has been proved that beclomethasone dipropionate is readily absorbed in the normal human skin. The main pathway of percutaneous absorption of beclomethasone dipropionate is proved to be trans-follicular route, but under plastic film a considerable amount of beclomethasone dipropionate is absorbed through the horny layer and the malpighian layer of epidermis. The basal layer of epidermis serves as a skin barrier for the percutaneous absorption of beclomethasone dipropionate through the normal skin.