Cancer immunotherapy has become recognized as a major step forward in the treatment of several types of cancer because it could allow for more targeted and individualized treatments. This chapter looks at how computational approaches are being used in the area of cancer immunotherapy. It addresses the past of this combination and how important it is to medical research currently. It focuses on the different ways computational methods are used in drug development, molecular models, and the development and enhancement of therapeutic agents like monoclonal antibodies, CAR T cells, and cancer vaccines. This chapter additionally highlights how significant insights were gained and what challenges had to be solved on the way from laboratory experiments to practical treatments for patients. The chapter addresses the difficulties and ethical concerns that come up when using computational techniques to treat cancer. The future of cancer treatment has great promise with the combination of big data, artificial intelligence, machine learning, customized medicine, and multi-omics. These new developments have the ability to make significant improvements in the field. This chapter is a comprehensive guide that delves into detail about how computer methods and cancer immunotherapy can be used together. It also covers the challenges and possible chances that lie ahead at this dynamic intersection.