Hemoglobin F, also known as fetal type hemoglobin, has a high concentration in the body during fetal life and gradually decreases after birth. The concentration of hemoglobin F in normal adults does not exceed 1%, but if the concentration of hemoglobin F increases significantly, it can be diagnosed as β-thalassemia, because when the concentration of hemoglobin F increases, it means that the synthesis of β-jugin peptide chain in the body is impaired, which means that β-thalassemia occurs. The higher the concentration of hemoglobin F, the more serious the β-thalassemia is, and the more obvious the patient’s symptoms are.