Hematologic disorders are diseases that occur in the blood cells or blood-forming organs. Hematologic disorders are a large group of diseases that include a variety of disorders. Common hematologic disorders: i. Red blood cell disorders, including erythropoietic disorders as well as erythropoietic disorders. The most common erythropoietic disorders are true erythropoietic disorders. Erythropoietic disorders include various anemic disorders, such as iron deficiency anemia, megaloblastic anemia, aplastic anemia, autoimmune hemolytic anemia, and thalassemia. Second, leukocyte system diseases, including leukocytosis, leukopenia and leukocyte malignancy various diseases, the most common is leukemia, including acute leukemia, chronic leukemia, etc. Third, immune system diseases, the most common is lymphoma, including Hodgkin’s lymphoma and non-Hodgkin’s lymphoma. Fourth, bleeding disorders, including immune thrombocytopenic purpura, allergic purpura, various types of hemophilia, diffuse intravascular coagulation, etc.