A high percentage of reticulocytes is usually due to iron deficiency anemia, hemolytic anemia and other conditions. Reticulocytes are the underdeveloped red blood cells in the human body, and their value reflects the hematopoietic function of the human bone marrow, which is mainly used to diagnose whether there is anemia in the patient, and to judge the effect of treatment for anemia. The high percentage of reticulocytes is mainly due to the low red blood cell index in the patient’s body, which stimulates the bone marrow hematopoietic function to continuously generate red blood cells, and is commonly seen in iron deficiency anemia, hemolytic anemia and other diseases. In addition to the above diseases, when patients with iron deficiency anemia are treated with vitamin B12, iron, folic acid and other medications as prescribed by the doctor, it will also lead to an increase in the percentage of reticulocytes in the body. Doctors often use this indicator to determine the therapeutic effect of the medication, so as to adjust the dosage of the medication according to the actual situation of the patient. To sum up, high reticulocyte percentage may be caused by anemia, or it may be a normal condition caused by anemia treatment.