The causes of nosebleeds in children include frequent nose picking, allergic rhinitis, nasal deformities, and other diseases. 1. Often picking the nose: children’s nasal mucosa is relatively weak, nasal blood vessels are abundant, if often picking the nose, resulting in the rupture of capillaries, thus the phenomenon of nosebleeds. If the amount of bleeding is not much, as long as you change the habit of picking your nose, you will relieve the symptoms of nosebleeds. 2. Allergic rhinitis: Especially in spring and fall, when the climate is dry and allergens are encountered, nosebleeds may occur. 3. Nasal deformity: such as curved nasal septum, can also cause nosebleeds, it is recommended to go to ENT department. 4. Other diseases: if repeated nosebleeds, and the bleeding is large, accompanied by weakness, pallor and other symptoms, to exclude malignant diseases of the blood system.