Immunotherapy is a type of treatment of a group of diseases, including cancer, that is based on the specific parts of the patient’s own immune system. Cancer immunotherapy aims to enable our immune system cells to target cancer cells and destroy them. Recently, cancer immunotherapy has become one of the most preferred drugs in cancer treatment. In cancer immunotherapy monoclonal antibodies, immune checkpoint inhibitors (ICI), cancer vaccines, oncolytic viruses, cytokine therapy and methods such as adoptive cell transfer come to the fore. Although these treatments are very promising for some types of cancer, they also have their own side effects.