Abstract： Objective To investigate the safety of rituximab combination chemotherapy in the treatment of B-cell non-Hodgkin' s lymphoma (B-NHL) complicated with hepatitis B virus (HBV) infection,and assess the incidence of HBV reactivation reduced by prophylactic lamivudine.Methods A retrospective study of HBV-related markers,HBV-DNA and liver function was performed before and after rituximabcontaining treatment in B-NHL patients.Thirty nine B-NHL patients with HBcAb(+)/HBsAb(-) were divided into prophylactic group (14 cases) and control group (25 cases).The incidences of HBV reactivation,functional damage of liver were measured.Results Among the 108 B-NHL patients who received rituximab combinatio nchemotherapy,15 (13.89 ％) were HBsAg (+) and 39 (36.11％) HBsAg (-) / HBcAb (+).Of the 15 HBsAg (+)patients,2 (13.3 ％) experienced reactivation of HBV.The prevalence of HBV reactivation was 7.7 ％(1/13) in patients who received prophylactic antiviral treatment and 50 ％ (1/2) in those who did not receivelamivudine.Among the 39 HBsAg (-) / HBcAb (+) patients,3 cases (7.7 ％) experienced reactivation of HBV.The prevalence of HBV reactivation was 0 in patients who receivcd prophylactic lamivudine treatment and 12 ％ (3/25) in those who did not receive this antiviral drug.Conclusion Prophylactic lamivudine before rituximab combination chemotherapy can reduce HBV reactivation obviously.