Chimeric Antigen Receptor (CAR)-T cell therapy is effective against B cell malignancies, but about 30% of non-Hodgkin lymphoma patients relapse due to resistance mechanisms such as reduced apoptotic sensitivity and CD19 loss. To address these limitations, we propose combining antibody therapy with CAR-T to enhance anti-tumor effects. Antibodies induce tumor cell lysis through Complement-dependent cytotoxicity (CDC) and antibody-dependent cellular phagocytosis (ADCP), independent of CAR-T’s granzyme/perforin pathway, and can target alternative antigens like CD20 or CD22 to overcome antigen escape. We first evaluated rituximab (anti-CD20) with CAR-T therapy and observed a significant increase in tumor lysis compared to either therapy alone. However, rituximab resistance, linked to CD55 upregulation, remains a challenge. To counter this, we tested a bispecific anti-CD20xCD55 antibody with CAR-T, which significantly improved tumor elimination in rituximab-resistant cells. Additionally, a CD20-targeting antibody combined with CAR-T effectively eradicated both CD19+ and CD19- lymphoma cells, overcoming antigen escape. In conclusion, antibody-CAR-T combinations enhance anti-tumor efficacy by overcoming resistance and antigen loss, supporting their clinical potential.