Abstract: This paper presents our recent results from a multiparameter observation of the anticancer activity of Luchasu (TP91) against mice tumor systems.TP91 was isolated from Chinese green tea.NIH mice were transplanted with S180 subcutaneously,and randomly divided into two groups,viz.,Luchasu (TP91) group and control group.Dosage of TP91 was 150 mg/kg/day,oral administration for seven days.control group received N.S. only.The results showed that Luchasu (TP91) possessed tumor suppressive effect.The inhibition rate for mice S180 was 436%.Luchasu (TP91) also inhibited growth of cultured Hela cells as well as EAC cells,as in vitro studies showed.Laboratory tests demonstrated that Luchasu (TP91) reduced blood coagulability,increased cAMP and SOD levels,and increased numbers of peripheral Tlymphocytes and stromal mast cells.Chemically,Luchasu (TP91) is a compound mainly contains EGCG and trace elements such as selenium and germinium.In the paper,mechanisms of action were discussed.It is of the authors opinion that Luchasu (TP91) is promising in chemoprevention and adjuvant therapy for human cancer.Further study is worth continuing.