Objective To observe the effect of Isorhamnetin on the cell senescence of colon cancer cell line SW48.Methods Different doses of Isorhamnetin were incubated with the SW48 cells,then the effect of Isorhamnetin on the apoptosis of SW48 cells was detected by Annexin V / PI assay,and the change of cell senescence was observed by β-GAL.The cell proliferation was measured by CCK8 assay and BrdU incorporation assay.Finally,the expression of cell senescence related proteins were detected by Western blot.Results The apoptosis rates of SW48 was remain similar when the concentration of Isorhamnetin was under 40nM,thus 10nM,20nM and 40nM Isorhamnetin were used in the further experiments.The cell senescence of SW48 cells was elevated after Isorhamnetin incubation for 48h,with cell proliferation reduced,and the expression of cell senescence related proteins was enhanced obviously.Conclusion Isorhamnetin may inhibit the proliferation and growth of cancer cells by promoting cell senescence.