About more than 70% of malignant tumor patients need radiotherapy. Some patients suffer from dietary disorders caused by the reaction to radiotherapy, which leads to a further decline in physical fitness, thus failing to withstand the torture of the disease, and ultimately bringing the anti-cancer treatment to a failure. Therefore, to ensure the smooth progress of radiotherapy, dietary support must be emphasized. Create a beautiful environment for patients and a favorable atmosphere for eating. Keep the indoor air fresh, pay attention to color, aroma, taste, shape and lightness in food processing, and appropriately accommodate the patients’ dietary habits to create a good eating mood. For patients with abnormal sense of taste and smell, seasonings can be added appropriately. In addition, family members should spend as much time as possible eating with the patient, so that the patient can increase the sense of affection and stimulate the desire to eat. Dry mouth, sore throat and esophagitis are the most common radiation reactions during radiotherapy for patients with head and neck or chest tumors, which are caused by radiation damage to salivary glands and mucous membranes. At this time, cool and non-irritating diet can be eaten, and hard and rough food can be avoided. The temperature of meals should not be too hot, meat should be chopped finely, and vegetables or fruits can be juiced if they cannot be swallowed. Those with dry mouth, sore throat and severe esophagitis can take or swallow a small amount of lidocaine solution before meals and then eat, the pain will be significantly reduced. Traditional Chinese medicine can be based on the patient’s dialectic respectively take the treatment principle of clearing heat and nourishing yin, nourishing yin, nourishing yin and moistening dryness, appropriate use of loquat leaves, maitake, avocado, lotus root juice, luo han guo, xuan shen, Sichuan pei and other traditional Chinese medicines. When abdominal radiotherapy, some patients will experience nausea and vomiting. Diet should be light and less greasy, eat small meals, put a small amount of ginger juice in the dishes to flavor, and try to avoid protein foods that are not fresh or smell strange. Bloating and diarrhea may also occur with abdominal radiotherapy. At this time, it is advisable to eat easy to digest, light, less greasy food, such as semi-fluid diet or less residue diet, avoid containing more fiber food and sticky, cold food. You can also assist in the use of some of the lowering and vomiting Chinese medicine such as Chen Pi, Faxia, Persicaria, Huo Xiang, Shen Xiang and so on. Some radiotherapy patients will be constipated, at this time, should be appropriate to increase the amount of activity. Eat more fresh vegetables, fruits and other foods rich in fiber, such as potatoes, sweet potatoes, apples, pears and so on. If necessary, take the traditional Chinese medicine Ma Ren Pills, and those without diabetes can also take it with honey and cool boiled water. Frequent urination, urinary urgency, urinary pain and hematuria are the symptoms of radiation cystitis, which often occurs during or after radiation therapy for pelvic tumors such as bladder cancer, prostate cancer, cervical cancer and rectal cancer. At this time, patients should drink more water and urinate more. In addition, add appropriate amount of baking soda to alkalize the urine, and diet therapy can use lemon slices to make tea. As radiotherapy can cause bone marrow suppression, manifested in the decline of white blood cells and platelets, etc.. In order to prevent bone marrow suppression caused by blood decline, pay attention to strengthen nutrition, appropriate more chicken, duck, fish, meat, etc., it is appropriate to use boiled, stewed, steamed and other methods of cooking. You can also choose foods with more iron, such as animal liver, waist, heart, egg yolk, etc.; vegetables such as spinach, tomato, celery, etc.; fruits can be given plums, pineapples, peaches, grapes, jujubes, prunes, oranges, tangerines and so on. Combined with some Chinese herbal stews that replenish the center and benefit the vital energy, the effect is even better: Codonopsis pilosula, Astragalus membranaceus, Senna, American ginseng, American ginseng, and so on.