Abstract: Objective: To study the expression and relationships of Bmi-1 and c-myc in diffuse large B-cell lymphoma (DLBCL) tissues and discuss their roles in carcinogenesis of DLBCL and explore their significances. Methods: The expressions of Bmi-1 and c-myc in 60 cases of DLBCL paraffins wax and 20 cases of benign lymph node lesions were detected by immunohistochemical method respectively. And the relationships of Bmi-1,c-myc and clinical parameters of DLBCL cases were analyzed. Results: The expression rate of Bmi-1 and c-myc in DLBCL was 65.0% and 75.0% respectively. Compared with the control, the difference was statitically significance(P < 0.05-P < 0.01). The expression of Bmi-1 and c-myc was related with clinical stage and international prognostic index(P < 0.05-P < 0.01),but there was no obvious correlation with its expression of the sex,age of patient,extranodal extension and clinical group(P > 0.05). Conclusions: Bmi-1 and c-myc had an synergistic effect in the development and progression of DLBCL and are useful in therapeutic and prognostic assessment.