Abstract: Objective :To explore the relationship between the metastasis of malignant tumor and erythrocyte immunodeficiency. Methods :Two kinds of mouse model were replicated. One is the model of erythrocyte immunodeficiency, another is the model of colonic cancer with liver metastasis established by splenic transplant of murine colon carcinoma 26. To observe the effects of abnormal erythrocyte immune function on liver metastases of colorectal carcinoma in the laboratory animals. The indicators of observation include erythrocyte C3b receptor rosette, erythrocyte immune complex receptor rosette, the capability of erythrocyte immune adherence to tumor cells, superoxide dismutase (SOD) and malondialdehyde (MDA). Results :Tumor metastases at different degree were observed among all groups of mice inoculated with tumor cells, in which the erythrocyte immunodeficiency group was significantly different from other groups (P<0.05). Abnormal function of oxidation and anti -oxidation was also observed among all groups of mice inoculated with tumor cells, in which the erythrocyte immunodeficiency group was significantly different from other groups (P<0.05). Conclusion :Tumor metastasis is very obvious in the state of immune dysfunction of erythrocyte. Low level of serum selenium and abnormal function of oxidation and anti-oxidation were associated with the immune dysfunction of erythrocyte.