stitute，Shanghai Medical University， Shanghai 200032，China） Abstract：In order to study the effects of tea polyphenols on cell growth and apoptosis of primary cultured rat skin keratinocytes， the safe dosage of tea polyphenols was determined by the release of lactate dehydrogenase(LDH). Cell counting(cytometry) and flow cytometry(FCM) were used to estimate the cell growth and the percentages of cells in different cell cycle phases or apoptosis. The results showed that tea polyphenols stimulated the cell growth from G1／G0 to G2／M phase， enhanced the synthesis of DNA(increase S phase) and increased the proliferative index(PI) from 18.17% to 25.62%. Also， it could block the occurrence of apoptosis. It is concluded that tea polyphenols could stimulate the growth of skin keratinocytes through stimulating the synthesis of cell DNA and inhibiting apoptosis.Key words