Radiotherapy is painful or not painful related to the radiotherapy site, and related to the size of the radiotherapy target area. Specifically as follows: 1, if the target area is very small, it is not too painful because the irradiation range is small and the patient does not feel anything at all after radiotherapy; 2, radiotherapy painful or not, mainly related to the site, radiotherapy bones such as legs, lumbar spine, arms, arms and legs are not painful, while the lumbar spine will be uncomfortable. Because when treating the lumbar spine, some people will have intestinal discomfort, some people have anorexia and other discomfort. When treating the brain, the side effects are actually the greatest, because patients with brain metastases have a combination of nausea and headache. After the administration of dehydration and cranial pressure lowering treatment, the related symptoms improve. The pre-radiation therapy can aggravate edema, and patients experience increased nausea and vomiting, which are also manifestations of radiotherapy discomfort. At this time, the amount of dehydration drugs can also be increased to reduce the patient’s discomfort. Radiotherapy to the lung is not uncomfortable if the radiotherapy area is small. If the radiotherapy is close to the mediastinum, radiotherapy to the mediastinal area will lead to radiation esophagitis, and some patients will experience such discomfort as painful swallowing. In addition, radiotherapy for gastrointestinal tumors, such as radiotherapy for gastric cancer and radiotherapy for pancreatic cancer, can damage the gastrointestinal tract and lead to discomfort such as reduced food intake and nausea. Therefore, whether radiotherapy is painful or not is related to the location, the size of the tumor and the target area. Each patient is in pain or not, and the specific kind of pain can only be consulted with the radiotherapist to inform the side effects of overall radiotherapy.