There are four common causes of headache, dizziness, nausea and vomiting in children. First, the child may have an upper respiratory tract infection, due to the invasion of bacteria or viruses, resulting in an infectious disease, which is manifested as headache, dizziness, nausea, vomiting symptoms. Secondly, the patient may have intracranial infection, viral encephalitis or bacterial encephalitis on top of the infection, which can only be clearly diagnosed under the examination of neurologist, and lumbar puncture of cerebrospinal fluid is needed to observe whether there is any elevation of leukocytes. Thirdly, the child needs to have a CT examination of the head to exclude intracranial space-occupying lesions and intracranial demyelinating lesions. Fourthly, the child may be suffering from gastrointestinal symptoms caused by an uncontrolled diet.