The main objective of this study was to investigate the effect of dietary fiber on anemia and glomerular filtration rate in non-dialysis patients with chronic kidney disease. Participants will be randomly divided into a dietary fiber intervention group and a blank control group. The patients in the dietary fiber intervention group will have dietary fiber intake survey conducted by dietitians on the basis of basic treatment. Supplemented dietary fiber was given on the basis of daily diet, once a day, 1 piece each time, before meals, and the intervention lasted for 3 months. The blank control group was followed up without intervention. Clinical data, blood, urine and stool samples were collected at the initial diagnosis and at each follow-up site.

Inclusion Criteria:

• Above 18 years old;
• Clinically confirmed (history, blood creatinine, kidney B-ultrasound, laboratory examination, etc.) as stage 3-5 chronic kidney disease, endogenous creatinine clearance was < 60ml/min according to Cockcroft-Gault formula;
• Generally in good condition, have a good understanding of their own illness and physical condition, have self-awareness, and can communicate well with others;
• Hemoglobin 100-130g/L;
• In a non-dialysis state.
• Dietary fiber intake <25g/d;
• Voluntarily join the study, understand the significance of the test and the indicators to be measured, and sign the informed consent.

Exclusion Criteria:

• Unwilling to join the study; Severe infection: fever, cough and sputum, pharyngeal pain, abdominal pain, diarrhea, carbuncle and other skin and soft tissue infection and other clinical manifestations, blood routine white blood cell count beyond the normal range (10×109/L);
• Severe cardiovascular diseases: including chronic cardiac insufficiency grade 3 or above and various arrhythmias;
• Obvious hypoproteinemia: albumin less than 30g/L;
• Corrective measures for anemia (blood transfusion, erythropoietin, HIF-PHI, iron supplement) have been applied in the past 3 months;
• Tumor evidence: certain tumors have been detected or clinical manifestations and tumor markers suggest the possibility of tumor;
• Pregnant women;
• Recent history of heavy blood loss.