Abstract: Objective: To evaluate the efficacy of the combination of Rituximab and chemotherapy in treating aggressive B-cell non-Hodgkin's lymphoma (B-NHL), and to analyze correlation factors of the response. Methods: We retrospectively ana-lyzed the data from 32 patients with aggressive B-NHL who underwent Rituximab combined with chemotherapy in our hospital. Results: Thirty-one patients were evaluable for objective response. The complete response(CR) rate was 64.5%,the partial response(PR) rate was 22.6%, and the overall response(OR) rate was 87.1%. In the 25 de novo patients, the CR rate was 80.0%, the PR rate was 20.0%, and the OR rate was 100%. While in the 6 recurrent or relapsed patients, the combination therapy achieved an OR rate of 33.3% and a PR rate of 33.3%. The median progression-free survival (PFS) time of the de novo patients and the recurrent or relapsed patients were 72.0(2~74) months and 7.2(1~12) months, respec-tively. The efficacy of treatment was influenced by Eastern Cooperative Oncology Group(ECOG) score(P<0.05). Serum lac-tate dehydrogenase(LDH) level, ECOG score, international prognostic index(IPI) score and chromosomal abnormalities were correlated with overall survival(OS) and PFS(P<0.05). B symptoms were correlated to PFS(P<0.05). Through COX regres-sion analysis, we found that PFS was influenced significantly by IPI score(P=0.01), and relative risk(RR) was 9.34. Con-clusion: Rituximab-containing chemotherapeutic regimens are effective for naive aggressive B-NHL and should be the first choice in the treatment for aggressive B-NHL with CD20 expression.