Radiotherapy is an effective local treatment, about 70% of tumor patients need radiotherapy, and it is widely used in tumor treatment with precise efficacy. Some tumors can be cured radically through radiotherapy, such as nasopharyngeal cancer, laryngeal cancer, malignant lymphoma, cervical cancer, skin cancer, etc.; most tumors can be improved and recurrence reduced through radiotherapy. According to traditional Chinese medicine, while radiation therapy kills cancer cells, it also disrupts the balance of yin and yang of the body and damages qi, blood and fluids, resulting in a series of toxic side effects in the whole body and local area. Systemic reactions are mainly manifested in fatigue, limb weakness, easy fatigue, dizziness and headache, drowsiness, slow reaction, insomnia, etc., as well as gastrointestinal reactions such as decreased appetite, nausea, vomiting, canker sore, diarrhea or constipation, and bone marrow suppression such as decreased white blood cells, thrombocytopenia and anemia. In Chinese medicine, radiation is considered a “fire evil”, which causes excessive heat toxicity in the body. Fire is a yang evil, which tends to injure fluid and consume qi, generate wind and move blood. Insufficient yin and fluid leads to the weakening of yang energy, resulting in the deficiency of both qi and yin, and the deficiency of qi leads to the weakening of yang energy. However, in patients with early manifestations or mild symptoms after radiotherapy, the signs of fire and heat are not very obvious. The many inflammatory symptoms that appear in the local reaction in the early stage of radiotherapy, such as dry nose and throat, wrinkled mouth and lips, less fluid on the tongue, dry cough without sputum, blood in sputum, dry stools or dry skin and unglorified hair, are more in line with the symptoms of warmth and dryness. With the increase of radiotherapy and the gradual accumulation of radiation dose, the toxic side effects of patients also increase accordingly, which is more in line with the characteristics of fire and heat causing disease, mainly showing the dryness of the deficiency of fluid and yin, and the deficiency of yin to carry qi, then qi deficiency, and the deficiency of qi drumming weakness then the poor blood flow causes blood stasis. Therefore, in clinical radiation therapy, the symptoms are mostly heat toxicity injury, Qi and Yin deficiency, spleen and stomach disorder, Qi deficiency and blood stasis, etc. The treatment is based on clearing heat and detoxification, moistening dryness and generating fluid, benefiting Qi and nourishing Yin, strengthening the spleen and stomach, benefiting Qi and invigorating blood, etc. The diet should also be chosen reasonably according to the different symptoms. According to the different sites of radiotherapy, the adverse reactions may also be different, and the dietary regimen is also different. （Head and neck tumors, including nasopharyngeal cancer and laryngeal cancer, often cause damage to the oral mucosa and salivary glands during radiation therapy, resulting in reduced secretion of salivary glands and dry mouth; congestion and edema of the mucosa of the mouth and throat, resulting in local pain and even ulcers. At this time the diet is very important, choose food to light, advocate cool, sweet and moist, nourishing yin and produce fluid food. The main food is rice, wheat and beans, and the meat is pork, duck, goose, turtle, oyster, clam, crab, etc. The vegetables should be fresh and tender, including radish, spinach, amaranth, mushroom, celery, wild rice, loofah, bitter gourd, bamboo shoot, etc., which contain more vitamin C and carotene. Watermelon, etc., can be supplemented with nutrients and has the role of nourishing yin and generating fluid. Watermelon, pear, etc. can also be taken orally in juice. （Chest tumors, such as esophageal cancer, lung cancer, breast cancer and mediastinal malignant tumors, are often seen as radioactive esophagitis and radioactive pneumonia during or after radiotherapy. Radiation esophagitis can cause mucosal congestion and edema in the esophagus, and in severe cases, it can lead to choking, mucosal ulceration, and pain behind the sternum when swallowing; radiation pneumonia can lead to dryness of the oropharynx and dry cough with little sputum. The above symptoms mostly belong to heat and toxin stagnation, dietary regimen with clearing heat and detoxification, moistening the lungs and resolving phlegm food, can choose yam, lotus seeds, fungus, lily, mulberry, tofu, red beans, duck,, turtle, dates, buttermilk, coix seeds, etc. Ice sugar lotus seeds and snow fungus (white fungus) soup, five rice porridge (raw barley kernel, walnut kernel, lotus seeds kernel, black sesame, rice, together grinded and cooked porridge) 1-2 times a day. Those who are weak can take snapper porridge (snapper, glutinous rice, meat soup, etc.). (3) Diet regulation of pelvic tumor radiation therapy Pelvic tumors, such as cervical cancer, rectal cancer, ovarian cancer, etc. in radiation therapy, radiation often damages the colon and rectal mucosa, resulting in intestinal wall mucosal congestion and edema, inflammatory cell infiltration, mucosal ulceration, etc. Clinically, it can be divided into acute radiation enteritis and chronic radiation enteritis. Acute radiation enteritis usually appears during or within 3 months after radiotherapy, mainly manifesting as acute and severe abdominal pain, perverse diarrhea, mucus stool or blood stool. Chronic radiation enteritis usually appears 3 months after the end of radiation therapy, and is characterized by intermittent diarrhea or increased frequency of stools, blood or mucus in stools, abdominal pain and anemia. Dietary care needs to be based on a moderate and balanced diet with small and frequent meals, high calorie and high protein to maintain a good nutritional status and avoid weight loss. For example, yam, onion, fresh amaranth, fresh lotus root, purple cabbage, eggplant, loofah, raw barley rice, red beans, etc. You can also use 20 grams of tea leaves fried yellow, 6 grams of ginger sliced, 1 head of garlic (crushed), add 150 ml of water and decoct for 20 minutes, put the right amount of brown sugar or honey and take orally, 1 to 2 times a day; or use several heads of garlic and fresh eggplant boiled together to make a dish to take, once a day; also use 100 grams of fresh amaranth and 50 grams of rice to cook porridge, once a day. It can also be taken with 100 grams of fresh amaranth and 50 grams of rice in porridge, once a day. Sun Simiao said: “All want to treat, gas to food therapy, both food therapy does not heal, then is the use of medicine. Chinese medicine believes that medicine and food are of the same origin, and mastering the appropriate diet not only has nutritional value, but also has a synergistic effect on radiation therapy, helping patients to improve their symptoms, increase their tolerance and successfully complete radiation therapy. In general, during the course of radiation therapy, one should consume foods with high protein, vitamins and calories as much as possible, as well as sufficient water, and can use semi-liquid diet or soft, easily digestible and nutritious foods, such as porridge, noodles, wontons, ice cream, milk shakes, put more seasonings in the cooking, and put more efforts in the color and aroma of food to stimulate the visual and smell senses to increase appetite, while the temperature of meals The temperature of the food should not be too hot. Meat is a good source of protein and should be finely chopped; vegetables or fruits should also be consumed, and if you can’t swallow them, you can squeeze them into juice. Avoid hot foods such as lamb, dog, meat, onion, ginger, garlic, yellow fish, crab, shrimp, orange, lychee, pomegranate, longan, fried, and strong alcohol. In addition, the patient can drink tea with mulberry leaves, chrysanthemum, wolfberry and raw licorice, or gargle with raw licorice and mint to reduce the pain caused by mouth ulcers. Finally, it should be emphasized that the patient should also work closely with your primary care physician to complete the treatment. Dietary therapy, an important part of Chinese medicine, is likewise a valuable heritage of Chinese splendid culture. Previous generations have summed up very rich experience in dietary therapy in practice, which is a supplement to pharmacotherapy and other therapies. Tumor dietary therapy is only an accumulation of some experiences so far, but with the development of science and in-depth research, the application of dietary therapy will become more and more extensive.