A patient with advanced and chemotherapy-refractory nodal marginal zone B-cell lymphoma was given a course of chimeric CD 20 monoclonal antibody Rituximab. Partial response was observed without any major toxicities. Retreatment with Rituximab for disease progression six months after the first course led to partial remission. Adjuvant radiotherapy was given for the residual disease and, currently, patient's disease remains stable eight months after the second course of Rituximab. This case demonstrates the therapeutic efficacy and feasibility of retreatment with Rituximab for relapsed or refractory low grade lymphoma.