Abstract: ObjectiveTo elucidate the effects of genistein on cancer or normal cell.MethodsThe inhibitory effects of genistein on the proliferation of human gatric cancer cell line SGC-7901,human lung cancer line YTMLC-90,Chinese hamster ovary cell line CHO and peripheral blood lymphocyte from healthy person were studied.ResultsThere are significantly inhibitory effects of genistein on proliferation of SGC-7901,YTMLC-90 and CHO cell line with a dose-effect and time-effect relationship.The lowest inhibitary concentration of genistein is 18.5μmol/L.Genistein affected the normal peripheral blood lymphocyte with a very slight extent.ConclusionGenistein inhibits the growth of tumor cells,so that it may have important significance in the treatment and prevention of cancer as a effective ingredient of health food.However,it is also found in this study that genistein was toxic to CHO cell line,and a further study is needed for the comphrehensive evalua2 tion of biological activities of genistein.