Abstract: The progress of molecular biology and tumor biology has greatly changed the mode of cancer treatment. A large number of scientific studies have revealed the mechanism of tumor immune evasion, and a variety of new types of tumor immunotherapy have emerged, which has become another effective treatment of cancer after surgery, radiotherapy, chemotherapy and targeted therapy. This paper introduces the mechanism of tumor cell immune evasion, and focuses on the design principle, biological drugs and the latest research progress of immunotherapy, such as cytokine immunotherapies, therapeutic monoclonal antibody immunotherapy, PD-1/PD-L1 therapy, CAR-T therapy, tumor vaccine, oncolytic virus and so on. At the same time, the advantages and disadvantages of various immunotherapies are compared to provide reference for drug research and development in tumor immunotherapy.