Abstract: Objective :To evaluate the efficacy of chemotherapy combined with highly agglomerative staphylococcin(HAS)for colon cancer. Methods :68 cases were randomized to receive chemotherapy combined with HAS(group A)and chemotherapy alone(group B).Oxaliplatin combined with FOLFOX4 was both used in two groups,and HAS was only used in group A. Results :The effect rate of group A Was higher than group B after 3 cycles(6 weeks)chemotherapy(P<0.05).Before chemotherapy in group B,CD3⁺was much higher,CD4⁺ and CD4⁺/CD8⁺ were obviously lower than those after chemotherapy(P<0.05).CD3⁺,CD4⁺ and CD4⁺/CD8⁺ had no significant difference before and after chemotherapy in group A.The major side effects were fever and phlebitis. Conclusion :HAS can reduce the immunosuppressive action caused by chemotherapy and enhance curative effect of colon cancer.