As an important intermediate link between in vitro cell experiments and clinical experiments, animal models are often preferred in researching tumor mechanisms, prevention, diagnosis, and treatment. The welfare of animals is closely related to the outcomes of animal experiments, serving as a crucial factor influencing the scientific validity and accuracy of research. Improving animal welfare can affect the reasonableness, feasibility, and ethical acceptability of animal experiments, thereby enhancing the reliability of research outcomes. This article summarizes the relevant aspects of experimental animals involved in tumor research, including tumor animal models, animal welfare related to tumor models, and humane endpoints.