Nosebleeds in children may be related to trauma, allergy, infection and developmental deformities of the nose. 1. Trauma: impact on the nose or regular nose picking may lead to trauma to the nose, which may cause capillary rupture and nosebleed. 2. Allergy: During the change of season, the weather is dry, and exposure to allergens such as pollen and dust mites can induce an allergic reaction in the body, which may also lead to nosebleeds in children. 3. Infection: Bacteria and other pathogenic microorganisms enter the nasal cavity, inducing acute and chronic rhinitis, sinusitis and other diseases. Chronic inflammatory stimulation can lead to the nasal mucosa in the state of bleeding edema, the child is also prone to nosebleeds. 4. Nasal developmental deformities: Suffering from nasal septum deviation and other diseases, the air circulation abnormalities may lead to nasal mucosa dryness, but also easy to lead to the rupture of capillaries, which leads to the child’s nosebleed. There are other clinical causes of nosebleeds in children. It is recommended to take your child to the ear, nose and throat department of a hospital to determine the specific cause of nosebleeds.