The treatment of anemia in 45-day-old babies is related to the cause of the disease, and treatment includes removing the cause, transfusing red blood cells, and preventing infection. Causes of anemia include nutritional anemia, hemolytic anemia, and aplastic anemia. 1. Nutritional anemia: including iron deficiency anemia and megaloblastic anemia. (1) Iron deficiency anemia: iron supplementation treatment, oral ferrous sulfate combination, correcting partiality and improving eating habits. (2) Megaloblastic anemia: those with psychoneurological symptoms should be treated with vitamin B12; if there is a lack of folic acid, folic acid should be taken orally, and vitamin C should be taken orally to help the absorption of folic acid. 2. Hemolytic anemia: infection should be prevented and folic acid should be supplemented appropriately. Prevention and treatment of hyperbilirubinemia can be light therapy or blood exchange therapy. Severe anemia can be transfused with red blood cells. If necessary, splenectomy is feasible. 3. Aplastic anemia: light anemia can be treated with symptomatic therapy, while medium and heavy anemia can be treated with symptomatic therapy, hematopoietic stem cell transplantation can be carried out in time to achieve radical cure. If children have anemia, they should go to the hospital in time to find out the cause of the anemia, and under the guidance of the doctor, treatment should be carried out. The above medications should be used under medical supervision.