A nosebleed is a symptom, which may or may not be pathological. One of the common reasons is local problems, such as bleeding caused by local mucosal rupture. Mucosal bleeding is generally related to dry nose caused by excessive internal heat. The second is bleeding from nasal polyps. The third is to check whether there are any blood diseases, which may cause bleeding because of thrombocytopenia, and the defect of coagulation factors can also lead to bleeding. In addition, nasal telangiectasia can cause bleeding. Therefore, anyone who has nosebleeds should look for the cause of bleeding and go to the hospital for an examination.