Nose bleeding in children is usually caused by the nasal mucosa being too dry, vitamin deficiency and inflammation and infection in the nasal cavity. 1. Nasal mucosa is too dry: If the nasal mucosa is dry, it may lead to dry crusts in the nasal cavity, which will lead to discomfort in the nasal mucosa, and children will often rub their hands or dig their nostrils, which will cause the nasal mucosa to rupture and cause nose bleeding. 2. Vitamin deficiency: vitamin C deficiency will reduce capillary fragility and permeability; vitamin K deficiency is related to the formation of plasminogen, which affects the coagulation mechanism; vitamin B₂ is involved in the enhancement of the repair of human skin and mucous membranes, therefore, once there is a nasal mucous membrane damage, and when the body is deficient in vitamin B₂, there will be recurrent nosebleeds. 3. Inflammatory infections in the nasal cavity: there may be some inflammatory secretions in the nasal cavity, which stimulate the nasal mucosa, and may also form dry crusts, which are attached to the surface of the nasal mucosa. All these factors are prone to lead to the occurrence of erosion and bleeding of the nasal mucosa, thus causing children’s nose bleeding. Children’s nose bleeding may also have other reasons, it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.