Children recently old nosebleed may be frequent nose picking, dry rhinitis, leukemia and other reasons. 1. Frequent nose picking: children lack of health concepts, frequent forceful nose picking, kneading the nose after the nasal mucosa capillary rupture bleeding; in addition to the hot and high-temperature environment, the air is dry and dehydrated is also prone to frequent nosebleeds. 2. Dry rhinitis: environmental abnormalities, climate change and other factors cause chronic inflammatory reaction of the nasal mucosa, mucosal cell secretion is reduced, dry congestive changes, capillary fragility increases, easy to blood vessel breakage and bleeding. 3. Leukemia: a common hematologic malignancy in children, a large number of malignant tumor cells proliferate in the bone marrow hematopoietic tissue, resulting in red blood cells, platelets and other generative disorders, coagulation dysfunction, so the old nosebleed. Children may also have other reasons for nosebleeds, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.