Nose bleeding at night may be caused by physiological factors such as dry environment and low water intake, as well as foreign bodies in the nasal cavity, deviated nasal septum, and other diseases such as leukemia. 1. Physiological factors: If the sleeping environment of the child is dry, or if the child has too little water intake during the day, the nasal mucosa of the child will be too dry, which will lead to the symptoms of nose bleeding at night. 2. Nasal foreign body: If the child puts a foreign body into the nasal cavity during the daytime play, and if the child rubs the nose at night, it will also lead to nose bleeding at night. 3. Deviated nasal septum: Deviated nasal septum is mainly caused by the underdevelopment of the bones in the nasal septum, and the main symptoms of the children are nasal congestion, headache, nosebleed, etc. In addition, children with deviated nasal septum may also have nosebleed at night. In addition, children with deviated septum will also have tinnitus and stuffy ears. 4. Other: leukemia, nasal tumor and other diseases can also lead to bleeding nose at night. There may be other reasons for babies to have nose bleeds at night, so it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, and then give targeted treatment or therapy.