Anemia is a decrease in the volume of red blood cells in the peripheral blood of the body. The criteria for the diagnosis of anemia in China is <120 g/L hemoglobin in adult males and <110 g/L hemoglobin in non-pregnant adult females at sea level. The common clinical types of anemia are mainly iron deficiency anemia, megaloblastic anemia, hemolytic anemia and aplastic anemia, and the clinical manifestations and treatments are mainly as follows: 1. Iron deficiency anemia: the clinical manifestations are mainly headache, dizziness, easy fatigue, weakness, blurred vision, and shortness of breath after activity. In case of anemia in children, symptoms such as growth retardation, mental retardation and xenophagia may appear. Physical signs may be pale skin and mucous membranes, dry hair, flat nails, etc. Treatment should actively find and remove the cause of iron deficiency, and follow medical prescriptions for iron supplements, such as ferrous sulfate, ferrous succinate, ferrous fumarate, etc. Treatment; 2. Megaloblastic anemia: clinical manifestations are dizziness, blurred eyes, weakness, abdominal distension, constipation, diarrhea, jaundice, tongue pain, etc. Patients with vitamin B12 deficiency may develop posterior spinal cord bundle degeneration, peripheral neuropathy, and psychiatric symptoms. The underlying disease should be actively treated, nutrition should be increased, folic acid or vitamin B12 should be supplemented, and intravenous infusion of red blood cells can be used for treatment if necessary. 3. Hemolytic anemia: clinical manifestations are low back pain and pain in the limbs, which may be accompanied by headache, chills, high fever, hemoglobinuria, jaundice and other symptoms. Glucocorticoids can be applied to treat immune hemolytic anemia and immune preparations can be applied to treat immune-related hemolytic anemia as prescribed by the doctor. 4. Aplastic anemia: Clinical manifestations include dizziness, blurred eyes, weakness, palpitations, pallor, skin mucous membrane bleeding, infection, etc. Some women may have excessive menstrual flow, and in severe cases, internal bleeding and sepsis may occur. Treatment includes removing the causative factors, controlling infection and bleeding, and following medical advice for multiple transfusions of component blood, hematopoietic cytokines in small doses, and high-dose transfusions of gammaglobulin. At the same time, androgens, cyclosporine and other drugs can be applied under the guidance of doctors. For patients with severe aplastic anemia, bone marrow transplantation or peripheral blood stem cell transplantation can be performed if necessary.