There are many reasons for the patient’s left brain headache, which need to be judged according to the patient’s age of onset, the course of the headache, the characteristics of the onset of the disease, and the relevant examination: the first aspect is that if the patient’s left brain pain lasts for a very long time and presents a chronic process of gradual progression and aggravation. In this case, it is necessary to consider that it is caused by intracranial tumor and intracranial space occupation, because the tumor will cause edema of brain tissue with the increase of time, and the tumor will hinder the circulation of cerebrospinal fluid, which can cause the patient to have chronic intracranial pressure increase, which will lead to the headache, and the patient may be accompanied by symptoms such as projectile vomiting or limb sensory disorder at the same time; Secondly, the patient who has frequent episodes of the left side of the brain presenting with a paroxysmal headache, Secondly, if the left side of the brain often suffers from paroxysmal headache and throbbing pain, it should be considered as vascular-neurological headache, which is most common in clinic, such as migraine, hypertension and other headaches; thirdly, if the patient suffers from prolonged headache, which is manifested as a sense of tightness, it should be considered as tension headache.