Sudden vomiting plus headache is a manifestation of intracranial disease leading to more narrowing of the cranial cavity, increase in the volume of brain parenchyma, inflammation, swelling and congestion leading to increased intracranial pressure. 1. Craniocerebral injury: cerebral contusion with cerebral edema, traumatic subarachnoid hemorrhage, etc. Suddenly the volume of brain tissue increases and leads to a sharp increase in intracranial pressure, and sudden vomiting and headache may occur. 2. Intracranial infection: acute inflammatory period such as purulent meningitis secretes a large amount of material, leading to a short-term increase in intracranial pressure and thus sudden vomiting and headache. 3. Acute cerebrovascular disease: hypertensive cerebral hemorrhage, subarachnoid hemorrhage will also appear sudden vomiting, headache. When sudden vomiting, headache should immediately go to the hospital, timely and clear cause, targeted treatment.