Humanized mice refer to model mice that carry human cells, tissues and organs into the body. The model constructed by transplanting human immune cells into immunodeficient mice is a humanized mouse model of the immune system. Can the immune system effectively rebuild the human immune system and better mimic the characteristics of the human body? The successful establishment of this type of model is to study the interaction between the immune system and tumors. Provide excellent experimental tools. To construct humanized mouse models of different types of immune systems? The advantages and disadvantages, and their applications in tumor immunotherapy have been reviewed?