Abstract: Objective To explore the influence of tea polyphenols (TP)on the apoptosis of human colon cancer cell line Caco-2 and RhoA protein activity.Methods The passage human colon cancer cell line Caco-2 cells were divided into experimental group and control group.The experimental was added with different concentrations of TP (25,50,100 and 200 μmol /L),while the control group was added with equal amount of culture fluid RPMI-1640.Inhibition of Caco-2 proliferation,ap-optosis indexes and RhoA protein activity within human colon cancer cell line Caco-2 cells were re-spectively detected by methyl thiazolyl tetrazolium (MTT),flow cytometry (FCM)and Pull-down method.Results Different concentrations of TP showed significant inhibitory effects on human colon cancer cell line Caco-2.Pull-down test results showed that TP could reduce the activity of RhoA pro-tein in human colon cancer cell line Caco-2 cells,and with the increasing of concentration,its protein activity decreased.Conclusion TP can promote the apoptosis of human colon cancer cell line Caco-2, which may be achieved by reducing the activity of RhoA protein.