Nosebleeds in small children may be caused by nasal dryness, nasal injury, nasal inflammation, blood diseases and so on. 1. Nasal dryness: generally in the fall and winter seasons, children’s nasal cavity is easy to appear dry, which makes the capillaries in the nasal cavity more fragile, easy to bleed. 2. Nasal injury: children like to pick their noses with their hands, but also due to curiosity will be all kinds of foreign objects into the nasal cavity, which will cause damage to the mucous membrane of the nasal cavity, resulting in the phenomenon of nosebleeds. 3. Nasal inflammation: some nasal inflammation is also easy to cause nasal mucosa, capillary expansion, nosebleed symptoms, such as allergic rhinitis, chronic simple rhinitis, dry rhinitis. 4. Blood diseases: Hemophilia, leukemia, thrombocytopenic purpura, aplastic anemia and other blood diseases may also cause spontaneous nasal bleeding. In addition to the above factors, it may also be caused by other reasons, it is recommended that when the symptoms persist, timely medical treatment for standardized treatment.