Leukemia is a type of common hematopoietic system tumor with fever, leukocytosis, anemia and hemorrhage as the main clinical symptoms. Leukemia can be divided into acute leukemia and chronic leukemia. TCM believes that leukaemia is closely related to latent pathogen and fire toxin. Based on the theory of "excessive qi is fire", this article believed that the pathogenesis of leukemia hemorrhage is the transformation of bone marrow pathological qi into fire, clarified the relationship between leukemia cells and "fire", and proposed that the basic principle of treatment should be strengthening the body and reduce fire, supplementing with methods such as clearing heat and detoxifying, tonifying qi and nourishing yin, so as to provide references for clinical treatment.