The anti-CD20 antibody has been broadly used in the treatment of B cell malignancies and exhibited good clinical outcomes. The CD19-targeted CAR-T has shown excellent therapeutic efficiency in B cell malignancies,especially in acute lymphocytic leukemia. However, patients treated with CD19-targeted CAR-T may face relapse of CD19 mutation. Therefore we attempt to treat Diffuse Large B Cell Lymphoma(DLBCL) patients by sequential therapy of the 2 targets and hope to combine their advantages.