In patients with nosebleeds, routine blood tests mainly look at the following items. The first point is hemoglobin, red blood cell count and hematocrit, mainly to see if the patient has anemia. If the patient has repeated nosebleeds, resulting in excessive blood loss in the patient’s organism, the above three items may be abnormal. Clinically, depending on the situation, if the patient’s hemoglobin is lower than 60g/L or less, it may be necessary to prepare for a blood transfusion. The second is to look at the platelet count. In some patients, if there is a significant decrease in platelets, then in this case, the patient is also prone to induce nosebleeds and needs to exclude the probability of having aplastic anemia, etc. In addition, some patients need to look at indicators such as the average pressure of red blood cells and the average red blood cell hemoglobin amount to determine whether the patient has thalassemia, which is not a common condition and can be roughly judged by these indicators. The third type is leukemia. If the patient has repeated nosebleeds and is found to have heterogeneous cells and a particularly high number of primitive naive cells through the examination, or if there are obvious abnormalities in the white blood cell count, lymphocyte count, neutrophil count, etc., it may suggest leukemia, and further examination is needed in this case. Of course, patients with nosebleeds should also have their coagulation function checked for factors such as coagulation factor deficiency.