Nosebleeds in children may be caused by factors such as environment, trauma and blood diseases. 1. Environment: When the air is dry, children’s nasal mucosa will be dry due to lack of moisture, and the blood vessels are more fragile, so it will be easier to have a nosebleed. 2. Trauma: If the children’s nose is hit by the outside world, or digging the nostrils and other phenomena will appear nosebleeds, mainly due to the more fragile capillaries in the nasal cavity, the external forces will cause the capillaries in the nasal cavity bleeding. 3. Blood diseases: children with coagulation disorders, thrombocytopenia and other diseases can lead to nosebleeds, which usually bleed more and for a longer period of time. Children may also have other reasons for nosebleeds, 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 treatment.