Hemolysis is a process in which various factors lead to the destruction of red blood cells and the overflow of hemoglobin, resulting in a shortened life span of the red blood cells themselves. When the bone marrow can compensate, it is called hemolytic state, which is divided into intravascular hemolysis and extravascular hemolysis; hemolytic anemia occurs when the hemolysis exceeds the compensatory capacity of the bone marrow. The more serious the disease, the greater the danger, both may be life-threatening: 1, intravascular hemolysis: red blood cells are destroyed in the blood circulation, mostly manifested as acute hemolytic anemia, such as paroxysmal sleep hemoglobinuria, patients often show more serious limb and low back pain, can be accompanied by headache, vomiting, chills, etc., with the development of the disease gradually appear high fever, hemoglobinuria, jaundice and other manifestations, and may even appear Peripheral circulatory failure or acute renal failure may occur, which is life-threatening. The occurrence of intravascular hemolysis is relatively urgent and needs to be treated in time to remove the precipitating factors and, if necessary, apply hormones and immunosuppressants as prescribed by the doctor, and consider transfusion therapy when the anemia is severe. The clinical manifestations are often anemia, jaundice, hepatosplenomegaly, etc. Long-term hyperbilirubinemia may damage the hepatobiliary function and may be complicated by cholelithiasis. Infection during this period may aggravate the hemolytic symptoms and lead to hemolytic crisis or aplastic anemia crisis, which may affect the patient’s life. This type of hemolysis has a slow onset and can be treated with hormonal therapy as appropriate. Splenectomy is also a common and effective treatment modality. Hemolysis can be caused by transfusion of incompatible blood types, stimulation by certain drugs, autoimmune system disorders, infection or incompatibility between the blood type of the newborn and the mother. Patients must seek timely medical attention, not only to treat the cause, but also to correct complications such as shock and electrolyte disorders in a timely manner.