Hemoglobin is controlled at 110-120g/L in patients on hemodialysis, and it is well known that renal anemia can occur in patients on dialysis. The reason for renal anemia is because the kidneys cannot secrete erythropoietin resulting in renal anemia. The reason why hemoglobin of hemodialysis patients is controlled at 110-120g/L, and the hemoglobin of normal people is >120g/L, is because the hemoglobin of dialysis patients is too high which can cause the blood pressure to rise, and the rise of blood pressure can cause some cardiovascular and cerebral vascular complications, such as cerebral infarction and cerebral hemorrhage. Too high hemoglobin can also cause an increase in blood viscosity, as we all know very well. Most of the hemodialysis patients complete hemodialysis by arteriovenous endovascular fistula, and the life expectancy of arteriovenous endovascular fistula life will be greatly shortened by the increase of blood viscosity. Increased blood viscosity can also cause other corresponding complications, such as cardiovascular complications, can cause cerebral infarction, myocardial infarction and other corresponding complications.