The routine blood indexes of iron deficiency anemia include red blood cell parameters, red blood cell count, hemoglobin count, reticulocyte count, etc. 1. Erythrocyte parameters: MCV (mean corpuscular volume of red blood cells) <80fl, MCH (mean corpuscular hemoglobin content of red blood cells) <27pg, MCHC (mean corpuscular hemoglobin concentration of red blood cells) <320g/L. 2. Number of red blood cells: the number of red blood cells in patients with iron deficiency anemia is often less than 4×10^12/L in men and less than 3.5×10^12/L in women. 3. Hemoglobin: Generally, adult male hemoglobin <120 g/L, adult female (non-pregnant) hemoglobin <100g/L is anemia. 4. Reticulocyte count: generally mildly increased in iron deficiency anemia, with a value of >1.5%, reflecting bone marrow compensatory hematopoiesis. Iron deficiency anemia cannot be diagnosed based on routine blood results, which only indicate that the patient has anemia, which is not necessarily caused by iron deficiency. Iron metabolism tests are needed to diagnose iron deficiency anemia. Abnormal laboratory results, it is recommended to consult a doctor in a timely manner, follow the doctor’s instructions to improve the examination, and active treatment.