Waking up with nosebleed may be related to dry rhinitis, deviated nasal septum, bleeding nasal polyp, tumor and so on. 1. Dry rhinitis: if you are in a dry environment for a long time, it is easy for the nasal mucosa to become dry and congested, and you may wake up with a nosebleed. 2. Deviated septum: if the nose is damaged or abnormal development, it may also appear as nosebleed, nasal congestion, headache and other symptoms, some people may wake up with nosebleed. 3. Nasal polyps: If you have nasal polyps, and at the same time, infection or allergy occurs in the nasal cavity, it may cause polyps to rupture, and there will be nosebleeds, and some people may wake up with nosebleeds. 4. Tumor: If benign or malignant tumor occurs in nasal cavity or sinus, it may also cause nosebleed when waking up. As you can see, there are many reasons for waking up with nosebleed, if this phenomenon has not been relieved or other uncomfortable symptoms, you should consult a doctor in time to find out the cause and under the guidance of the doctor for treatment.