Objective: To observe the influence of human mutant p27 gene (p27mt) on the growth and apoptosis of colon can-cer cells so as to investigate the function mechanism of p27mt in gene therapy for colon cancer. Methods: Colon cancer cell line SW480 was infected with recombinant replication defective adenovirus Ad-p27mt, and expression of p27mt protein was detected by Western blot; the inhibition effect of p27mt on SW480 cells was detected with cytometry. Cell cycle was decided with flow cytometer, and DNA fragment analytic process identified the occurrence of apoptosis. Results: After transfected SW480 cells with Ad-p27mt, high expression of p27 protein was identified with immunoblotting assay. PI staining and flow cytometer assay showed 77.96% colon cancer cells was blocked in phase G0/G1, while in Ad-LacZ group and blank control group, 27.57% and 25.29% cells were blocked in the same phase, respectively. Growth curve showed Ad-p27mt has an obvious inhibition effect on the growth of SW480 cells, DNA fragment assay demonstrated that p27mt was able to induce the apoptosis of colon cancer cells. Conclusion: p27mt has an obvious blocking effect on colon cancer cell cycle, and most cells were blocked in phase G0/G1. This blockage is related with the growth inhibition and apoptosis induction effect of p27mt. Objective: To observe the influence of human mutant p27 gene (p27mt) on the growth and apoptosis of colon can-cer cells so as to investigate the function mechanism of p27mt in gene therapy for colon cancer. Methods: Colon cancer cell line SW480 was infected with recombinant replication defective adenovirus Ad-p27mt, and expression of p27mt protein was detected by Western blot; the inhibition effect of p27mt on SW480 cells was detected with cytometry. Cell cycle was decided with flow cytometer, and DNA fragment analytic process identified the occurrence of Results: After transfected SW480 cells with Ad-p27mt, high expression of p27 protein was identified with immunoblotting assay. 77.96% of colon cancer cells were blocked in phase G0 / G1, while in Ad-LacZ group and blank control group, 27.57% and 25.29% cells were blocked in the same phase, respectively. Growth curve showed Ad-p27mt has an obvious inhibition effect on the growth of SW480 cells, DNA fragment assay demonstrated that p27mt was able to induce the apoptosis of colon cancer cells. Conclusion: p27mt has an obvious blocking effect on colon cancer cell cycle, and most cells were blocked in phase G0 / G1. This blockage is related with the growth inhibition and apoptosis induction effect of p27mt.