Novel approaches to tumor immunotherapy include adoptive cell immunotherapy, immune checkpoint inhibitors (ICIs), and bispecific antibodies (bsABs). bsABs are members of the antibody family that have the ability to distinguish between two distinct antigens or epitopes on a single antigen. These antibodies show better clinical results than monoclonal antibodies, suggesting that they might be a useful choice for tumor immunotherapy. Additionally, dual blockade immunotherapy targeting PD-1/PD-L1 and CTLA-4 functions at various phases of T cell activation with synergistically increasing immune responses against cancer cells, in contrast to ICI monotherapy, which sometimes displays treatment resistance and limited effectiveness. It has been shown that immune response rates and anti-tumor effects may be increased in a synergistic manner by ICI-based combination therapy. We explore the safety and effectiveness of bsABs and ICIs (especially PD1/PDL1 and CTLA-4) combination treatments in tumor immunotherapy in this study with the goal of offering evidence-based methods for clinical research and tailored tumor identification and management.