When a patient has nose bleeding, leukemia can be ruled out by bleeding symptoms, blood count and bone marrow aspiration.1. Bleeding symptoms: The clinical symptoms of leukemia patients are usually spontaneous bleeding, high bleeding volume, difficulty in stopping oneself and repeated nosebleeds. There is also a tendency to bleed from multiple parts of the body, such as petechiae on the skin, bleeding from the gums, and in some patients, bleeding from the urinary tract, or even brain bleeding, etc. In addition, patients with leukemia, especially acute leukemia, usually have a low-grade fever or a high fever of 39-40°C, with a tendency for infection or multiple infections. At the same time, patients will have enlarged lymph nodes and enlarged spleen, and some patients will also show skeletal pain, such as pain in the bones and joints of the sternum and legs; 2. Routine blood count: The platelets and white blood cells in the routine blood count of leukemia patients will indicate abnormal levels, and the white blood cell count and the ratio of white blood cells are also in abnormal, and in the classification of white blood cells, primitive and naive white blood cells can be seen; 3. Bone marrow aspiration: When the above abnormalities occur and the routine blood results are abnormal, patients are advised to visit the hematology department for a bone marrow examination to further confirm the diagnosis. The common cause of nosebleeds is not leukemia, but dryness of the nasal cavity and abnormalities of the nasal structure, such as deviated nasal septum, atrophic rhinitis, dry rhinitis and nasal masses, or possibly hemangioma or malignant tumor of the nasal cavity or nasopharyngeal cancer. Some patients with hypertension may also cause recurrent bleeding from the nasal cavity.