This study explores the development and efficacy of bispecific BCMA/CD24 CAR-T cells in treating multiple myeloma (MM). Anti-BCMA CAR-T cell therapies have shown high response rates but are often followed by relapse due to the presence of minimal residual myeloma cells. These residual cells often exhibit stem-like features and express CD24, a checkpoint molecule that inhibits macrophage phagocytic clearance. The study generates CD24-CAR-T cells to target and eliminate these residual myeloma cells by blocking the CD24-Siglec-10 pathway, enhancing macrophage phagocytic activity. In vitro and in vivo experiments demonstrate that CD24-CAR-T cells effectively reduce MM cell burden, promote macrophage polarization towards an M1-like phenotype, and improve survival in a mouse model of MM. Bispecific BCMA-CD24-CAR-T cells, which target both BCMA and CD24, further enhance cytolytic activity and survival in vivo. This work presents a promising immunotherapeutic approach to target MM cells and promote tumor cell clearance by macrophages, offering a potential solution to the issue of durable cures following BCMA-CAR-T therapy.This study explores the development and efficacy of bispecific BCMA/CD24 CAR-T cells in treating multiple myeloma (MM). Anti-BCMA CAR-T cell therapies have shown high response rates but are often followed by relapse due to the presence of minimal residual myeloma cells. These residual cells often exhibit stem-like features and express CD24, a checkpoint molecule that inhibits macrophage phagocytic clearance. The study generates CD24-CAR-T cells to target and eliminate these residual myeloma cells by blocking the CD24-Siglec-10 pathway, enhancing macrophage phagocytic activity. In vitro and in vivo experiments demonstrate that CD24-CAR-T cells effectively reduce MM cell burden, promote macrophage polarization towards an M1-like phenotype, and improve survival in a mouse model of MM. Bispecific BCMA-CD24-CAR-T cells, which target both BCMA and CD24, further enhance cytolytic activity and survival in vivo. This work presents a promising immunotherapeutic approach to target MM cells and promote tumor cell clearance by macrophages, offering a potential solution to the issue of durable cures following BCMA-CAR-T therapy.