Headache and nausea in children may be related to upper respiratory tract infection, concussion, intracranial infection and so on. 1. Upper respiratory tract infection: it may be a virus or bacteria invading the organism, producing a large number of toxins causing fever. It leads to the dilation of blood vessels in the brain to show symptoms of headache, which may also be accompanied by nausea and dizziness. 2. Concussion: It may be that the child’s head is hit by certain impact while playing, causing a concussion, which may also cause headache and nausea. 3. Intracranial infection: for example, meningitis, a diffuse inflammatory change of the meninges caused by bacterial, viral, fungal and other pathogens, usually accompanied by fever, headache, nausea and other symptoms. Headache and nausea in children can also be seen in other causes, it is recommended to consult a doctor in a timely manner, comply with the doctor’s instructions to carry out relevant examinations, with the help of the doctor to clarify the cause, and targeted treatment or treatment.