The main causes of nosebleeds in children are as follows: 1. The most common one is allergic rhinitis, which is usually accompanied by allergic constitution, and allergic substances tend to increase the brittleness of capillaries in the nasal mucosa, leading to bleeding. 2. picking nostrils and so on, which leads to the rupture of capillaries in the nasal mucosa, resulting in bleeding. The above mentioned causes are the main reasons for nosebleeds, and the solutions are: 1) to get rid of the allergic environment; 2) to keep the nasal mucosa moist; 3) to improve the bad habits. The above points can avoid or reduce the possibility of nosebleeds in children.