Red blood cell 55 should say that the hemoglobin level is 55g/L, which belongs to severe anemia, this condition may be related to blood disease, anemia and other diseases, or very serious. The normal values of hemoglobin are 120-160g/L, 110-150g/L, 170-200g/L for adult males, females, and newborns respectively. hemoglobin 55g/L indicates severe anemia. The possible diseases causing this condition are as follows: 1. Bone marrow hematopoietic abnormalities: such as aplastic anemia, leukemia, etc. 2. Red blood cell destruction: e.g. Mediterranean anemia, liver cirrhosis, hypersplenism, etc. 3. Hemorrhagic anemia: such as chronic peptic ulcer, trauma, major surgery and so on. In addition to the above conditions, iron deficiency anemia, malignant tumors and other diseases may also cause the above conditions. It is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, and then give targeted treatment or treatment under the guidance of the physician.