The article provides an overview of recent advancements in cancer immunotherapy, highlighting the clinical successes of immune checkpoint blockade and chimeric antigen receptor (CAR) T cell therapies. These therapies have marked a turning point in cancer treatment, emphasizing the importance of understanding tumor immunology for effective clinical translation. The review covers key aspects such as the dual role of the immune system in cancer, the mechanisms by which tumors evade immune recognition, and the development of immunosuppressive myeloid cells in the tumor microenvironment. It also discusses the clinical efficacy and challenges of immune checkpoint therapy, CAR T cell therapy, and therapeutic cancer vaccines. The article concludes by emphasizing the need for continued research to improve the understanding of tumor immunology and develop more effective cancer therapies.The article provides an overview of recent advancements in cancer immunotherapy, highlighting the clinical successes of immune checkpoint blockade and chimeric antigen receptor (CAR) T cell therapies. These therapies have marked a turning point in cancer treatment, emphasizing the importance of understanding tumor immunology for effective clinical translation. The review covers key aspects such as the dual role of the immune system in cancer, the mechanisms by which tumors evade immune recognition, and the development of immunosuppressive myeloid cells in the tumor microenvironment. It also discusses the clinical efficacy and challenges of immune checkpoint therapy, CAR T cell therapy, and therapeutic cancer vaccines. The article concludes by emphasizing the need for continued research to improve the understanding of tumor immunology and develop more effective cancer therapies.