Hemoglobin 99 is hemoglobin 99g/L, which is classified as mild anemia. Anemia is more common and is usually identified if the hemoglobin is <110g/L for women, <120g/L for men and <100g/L for pregnant women. According to the severity, mild anemia hemoglobin>90g/L, moderate anemia hemoglobin is 60~90g/L, severe anemia hemoglobin<60g/L, hemoglobin<30g/L belongs to the very severe anemia. Therefore hemoglobin 99g/L belongs to mild anemia. The causes of mild anemia are physiological and pathological, physiological, such as menstrual bleeding, resulting in mild anemia; pathological, such as the lack of folic acid, vitamin B₁₂ resulting in megaloblastic anemia, or such as chronic enteritis resulting in iron-deficiency anemia, but also can be seen in aplastic anemia, acute leukemia and so on. It is recommended to go to the hospital in time to identify the cause of the disease, and under the guidance of the doctor to give the corresponding treatment and treatment.