In recent years, the incidence of tumor in the city has been increasing year by year. However, most patients do not arrange their diet reasonably while getting regular treatment, which makes the treatment effect be affected to some extent. Tumor will cause excessive consumption of nutrients in the body. When suffering from tumor, patients will often show symptoms such as wasting and weakness, and their immunity also decreases, especially when experiencing a series of treatments such as surgery, radiotherapy and chemotherapy, the body is more depleted, and a good diet structure must be used as the basis to achieve ideal treatment effect. The ancients said, “Poison attacking evil, five grains for nourishment, five fruits for help, five animals for benefit, five dishes for filling, the smell combined and served to replenish the essence.” It means that the diet of cereals, fruits, meat and vegetables is very important to assist the treatment of diseases. So how should tumor patients “eat”? First of all, to ensure a balanced diet structure. Many tumor patients have raised the issue of “avoiding food”, thinking that fish, shrimp, chicken and eggs are “hairy” and cannot be eaten after suffering from tumor. This has no scientific basis. Secondly, to ensure the high quality of dietary elements, that is, high energy, high protein, high vitamin and high fiber. Rice and noodles are the main sources of carbohydrates for human body, foods rich in protein include fish, poultry, eggs, beans and dairy, etc. Vegetables and fruits are rich in vitamins. Thirdly, tumor patients, especially after undergoing radiotherapy and chemotherapy, their appetite and digestive and absorption functions are affected to a certain extent, so they should pay attention to eating less and more meals, try to eat some easily digestible food, and pay attention to improving the color, aroma and taste of food to stimulate their appetite. Finally, tumor patients should quit smoking and alcohol, don’t eat spicy, hot and other stimulating food, and don’t eat too cold or too hot food. As the saying goes, “medicine is better than food.” Many patients, after falling ill, simply buy a lot of health care products to take, which not only consumes a lot of financial resources, but also may not achieve the desired effect. Under the guidance of doctors, a reasonable combination of diet and a balanced diet structure will be very beneficial to the treatment and recovery of tumor patients.