Nosebleed when sneezing may be caused by deviated nasal septum, dry rhinitis, allergic rhinitis and other diseases. 1. Deviated nasal septum: Deviated nasal septum is caused by the dysplasia of the bones of the nasal septum, and the main symptoms of patients are nasal congestion, headache, nosebleed, etc. The sharpness of the mucous membrane at the deviated nasal septum can be caused by excessive nerve tension. When the mucous membrane at the deviated nasal septum is sharp, it may cause sneezing after stimulation by external factors due to excessive nerve tension. 2. Dry rhinitis: dry nose is mainly a chronic inflammation of the nasal mucosa, often associated with climate, environment and other factors. The main symptoms of patients are nasal dryness, nasal tingling and itching sensation, nasal bleeding, etc. Dry rhinitis will also appear nasal irritation, nasal filamentous secretion and other symptoms. 3. Allergic rhinitis: this disease is often due to allergen stimulation after continuous sneezing symptoms, due to mucosal inflammatory congestion, edema, mucosal brittle changes, in blowing the nose and sneezing easily lead to rhinorrhea. Patients who have nosebleeds when sneezing should go to the hospital in time to find out the cause of the disease and follow the doctor’s instructions for treatment.