Children have nosebleeds in the summer, considering the dryness of the nasal cavity, allergic rhinitis, nasal hemangioma and other causes. 1. Nasal dryness: the air may be dry in summer, children drink less water, sweat more, resulting in the nasal mucosa is also dry, the fragility of capillaries increases, it is easy to break and bleed. 2. Allergic rhinitis: in the summer if allergic to certain substances, such as pollen, may lead to allergic rhinitis in children, due to the itchy nose often rubbing the nose is also easy to lead to nasal mucous membrane breakage bleeding. 3. Nasal hemangioma: there may be hemangioma in the nasal cavity, and it is easy to rupture in summer because it is more fragile, resulting in nosebleeds. Nosebleeds in summer may also be caused by other reasons, it is best to go to the hospital to clarify the cause.