Side headache is mainly considered to be caused by the following aspects: 1. If it is paroxysmal throbbing pain, swelling pain or throbbing-like pain, it should be considered to be migraine. Migraine headache can easily recur in clinical situations because of poor sleep, fatigue, mental tension and dietary stimulation, and in serious cases, there will be nausea, vomiting, fear of light, fear of sound and some of these manifestations; 2. If the patient has a headache on one side, there is a possibility that poor sleep and mental tension may cause the patient to have a side headache due to neurological weakness; 3. If the headache on one side is in the posterior occipital region, it should be considered as occipital neuralgia, auricular neuralgia and neuralgia. Neuralgia is usually caused by low resistance, cold or viral infection; 4. If the headache on one side of the patient lasts for a long time, accompanied by sensory disorders of the limbs, motor disorders or dizziness and other symptoms, it should be considered to be caused by intracranial tumors or intracranial occupying lesions.