Abstract: The eaTect of anthralin on the growth of epidermal keratinacytes in culture was studied. cultured epidermal cells were treated by antlualin at the concentration of 10μg/ml for 15 minutes, 1 hour and 24 hours, the inhibitory effect on DNA replication of epidermal cells were 43%, 61% and 92% repectively the inhibition on mitotic activity of epidermal cells were 68%s 84% arid 91% respectively. It is an experiment to prove that minute-therapy with anthralin for psoriasis is reasonable. The mecktauism of the inhibition of the growth of epidermal cells by antltxalin was discussed.