The exact cause of leukemia is currently unknown. Many factors are thought to be related to the development of leukemia, such as biological factors, physical factors, chemical factors, genetic factors, and the development of other diseases. 1. Biological factors: may be the main factors, including viral infection and abnormal immune function, such as human T-lymphotropic virus type I can lead to adult T-cell leukemia. Some people with abnormal immune function have an increased risk of developing leukemia. 2. Physical factors: including X-rays, γ-rays and other ionizing radiation. Some studies have shown that large areas and large doses of ionizing radiation can lead to leukemia. 3. Chemical poisons or drugs and other factors: such as benzene and organic solvents containing benzene, ethylenediamine, and certain antitumor drugs, etc., all have a leukemia-causing effect. 4. Genetic factors. 5. Others: the development of hematologic diseases such as myelodysplastic syndromes, lymphoma, multiple myeloma, paroxysmal sleep hemoglobinuria, etc., may eventually develop into leukemia. For specific knowledge, consult a hematologist.