Bilateral nosebleeds can not be stopped because of acute leukemia, aplastic anemia, nasopharyngeal fibroangioma and other causes. 1. Acute leukemia: the common clinical manifestations of all types of acute leukemia are mostly related to the inhibition of normal hematopoietic cell production and the proliferation and infiltration of leukemia cells. The mechanisms of bleeding are as follows: ① thrombocytopenia; ② vascular wall damage; ③ coagulation disorders; ④ increased anticoagulant substances. 2. Aplastic anemia: the vast majority of clinically diagnosed primary acquired retroviruses are autoimmune diseases whose target organ is the bone marrow, eventually causing bone marrow failure. This leads to a decrease in the production of bone marrow hematopoietic stem/progenitor cells and tertiary blood cells, and a decrease in the number of whole blood cells in the peripheral blood, which leads to a tendency to hemorrhage and is difficult to stop. 3. Nasopharyngeal fibrous hemangioma: the tumor body consists of collagen fibers and multinucleated fibroblasts that form a reticular matrix, between which are distributed a large number of thin-walled blood vessels without contraction ability, which will bleed easily when damaged. Patients who have more than one nosebleed should go to ENT department in time for systematic examination and clear diagnosis.