The current treatment of tumor is mainly three major tools, surgery, radiotherapy. Chemotherapy. Chemotherapy. With the development of radiobiology, oncology and medical computer, the status of radiation therapy in tumor treatment is also increasing. About 60-70% of tumor patients need to receive radiation therapy for different purposes at different times. The clinical cure rate of general tumor is 45%, surgery is 22%, radiotherapy is 18% and chemotherapy is 5%. It can be seen that radiotherapy is similar to surgery. Radiation therapy is divided into radical radiotherapy (e.g. nasopharyngeal cancer, laryngeal cancer, skin cancer, lymphoma, seminoma, etc.) and palliative radiotherapy (bone metastasis, pain relief, superior vena cava compression syndrome, hemorrhage, etc.) according to the purpose of treatment, and combined with other means, it is divided into simple radiotherapy, preoperative, intraoperative and postoperative radiotherapy. In combination with other means, radiotherapy is classified as simple radiotherapy, preoperative, intraoperative and postoperative radiotherapy, and simultaneous radiotherapy and chemotherapy, thermal radiotherapy, etc. The treatment of various tumors requires the participation of radiotherapy.