The diagnostic criteria of aplastic anemia mainly include: blood routine shows complete blood cell reduction, bone marrow aspiration shows hematopoietic cell reduction, exclusion of hepatosplenomegaly, exclusion of other diseases causing complete blood reduction, and ineffective anti-anemia treatment. Aplastic anemia is a bone marrow hematopoietic failure disease, which is a syndrome of anemia, infection, bleeding and a series of other symptoms due to low hematopoietic function of bone marrow, and its diagnostic criteria include the following five points. 1. Blood routine: peripheral blood has a decrease in whole blood cells, a percentage of reticulocytes less than 1%, an increase in the percentage of lymphocytes, and a decrease in the percentage of neutrophils. 2. Bone marrow aspiration: it may reveal hypoproliferative bone marrow in multiple sites, decreased percentage of hematopoietic cells, and increased percentage of non-hematopoietic cells. 3. Rule out hepatosplenomegaly: usually there is no hepatosplenomegaly, which can be clarified by ultrasound. 4. Excluding other diseases that cause hypoperfusion: e.g. acute leukemia, myelodysplastic syndrome, etc. 5. Ineffective anti-anemia treatment: general anti-anemia treatment such as iron supplementation, folic acid supplementation and vitamin B12 is ineffective, and only through immunosuppressive treatment such as cyclosporine can be effective. For patients with aplastic anemia, once the diagnosis is confirmed, they need to consult a doctor in a timely manner, and actively carry out treatment under the guidance of the doctor.