Patients with chronic renal failure have a series of symptoms due to the accumulation of toxins in the body because the kidneys cannot effectively remove the metabolic wastes produced by the body due to the diminished effective filtration function of the glomerulus. In order to reduce the damage of toxins to the body, on the one hand, we should strengthen the removal of toxins, on the other hand, we should reduce the intake of toxin-producing nutrients to reduce the burden on the kidneys as much as possible. For this reason, the dietary treatment of patients with chronic renal failure is very important. I. Non-dialysis patients: The overall principle is low salt, high quality low protein, low phosphorus and low purine diet. Excessive salt intake causes sodium and water retention, resulting in edema and hypertension; in addition, excessive salt intake affects the efficacy of antihypertensive drugs. Low-salt diet is the basic treatment for patients with chronic renal failure and is recommended to be controlled at 3-6g/d. Those who have edema should be more strictly salt restricted. High quality low protein diet, on the one hand, can ensure the normal metabolism of the body, not to occur malnutrition, on the other hand, can reduce the burden on the kidneys, so that the uremic toxins are not too much. So what is high quality protein? The merit of protein is determined by the type and content of amino acids in the constituents of protein. Generally speaking, if the protein in food is rich and complete in essential amino acids, in the right proportion, easily digested and absorbed by the body, and has a high utilization rate after absorption, we call it high-quality protein. Usually, animal foods (such as milk, eggs, fish, livestock meat, etc.) are rich in high-quality protein. On the contrary, plant-based foods contain less high-quality protein. Cereals are the main source of calories for the body, but cereal protein is non-high quality protein and has a medium protein content. Therefore, in order to ensure adequate calorie and high-quality protein intake, it is better to replace cereals in the main diet with wheat starch on the basis of total protein restriction to ensure more than 50% of high-quality protein intake per day to achieve the purpose of balancing the body’s needs. Currently, it is advocated to decide the protein intake according to the glomerular filtration rate. gfr<50m1 min="" gfr="">20m1/min, 5g can be added daily, if gfr<5m1/min, about 20g of high quality protein should be consumed daily. In addition, treatment with compounded alpha keto acid (Kaito) can be added to a protein-restricted diet. Phosphorus is abundant in nature, and various foods basically contain phosphorus. In particular, animal foods and nuts are high in phosphorus. Phosphorus is water-soluble, and under normal conditions, most phosphorus is excreted by urine. As kidney function decreases, phosphorus accumulates in the body, causing disorders of calcium and phosphorus metabolism and finally chronic kidney disease-mineral and bone metabolism disorders (CKD-MBD). The causes of hyperphosphatemia include excessive ingestion, reduced excretion and disturbances in the levels of hormones affecting bone mineral metabolism, such as active vitamin D. For this reason, it is recommended to control the daily intake of phosphorus in patients with chronic renal failure to 800-1000 mg. Since phosphorus is water-soluble, patients are advised not to drink soup with high phosphorus content, and are advised not to consume phosphorus-rich foods such as nuts, animal offal and soy products. Low purine diet. In patients with chronic renal failure, uric acid is usually also increased due to impaired uric acid excretion. In addition to causing gout, hyperuricemia also causes endothelial damage to blood vessels. Uric acid is the end product of purine metabolism. It has been found that high levels of uric acid are directly proportional to the purine content within food. For this reason, patients with chronic renal failure should adopt a low purine diet. According to the content of purine in food, we can classify food into low purine food (less than 25 mg of purine per 100 grams of food), medium purine food (25-150 mg of purine per 100 grams of food) and high purine food (150-1000 mg of purine per 100 grams of food). High purine food mainly includes: animal offal, seafood, sardines, anchovies, scallops, arks, clams, chicken soup and broth. Gout patients should be prohibited from eating these foods. Medium purine food mainly includes: poultry and livestock meat, fish, shrimp, crab, eel, white fish, flat fish, silver carp, various kinds of beans and peanuts, sesame seeds, etc.. Gout patients should try to eat less of these foods. In addition, some vegetables also contain high purine, such as leeks, cauliflower, soybean sprouts, pea shoots, lentils, cauliflower, purple cabbage, mushrooms, etc., it is best not to eat or eat less. Foods containing less purines include eggs, duck eggs, milk, cheese, etc. Second, dialysis patients: For dialysis patients, the overall principle is basically the same as non-dialysis patients. As dialysis treatment is taken, in order to ensure adequate nutrition and make up for the loss of dialysis and ensure positive nitrogen balance, protein intake should be increased, with quality protein intake at 1.0-1.2g/kg/d for hemodialysis patients and 1.2-1.4/kg/d for peritoneal dialysis patients. Of course, chronic Renal failure patients, regardless of whether they are on dialysis or not, should firstly be treated on the basis of ensuring systemic basal metabolic needs and sufficient calories, and high calorie foods can be given appropriately according to their conditions. In conclusion, diet therapy for chronic renal failure is the foundation of the whole treatment and needs to be adhered to for a long time. On this basis, combined with other therapeutic measures to delay the deterioration of renal function, it can effectively protect the renal function of patients and improve the prognosis.