There are many reasons for frequent half-sided headache, which can be analyzed by doing examination and the nature of headache, as follows: First, if the patient is showing throbbing pain on one side of the head, triggered by emotional tension, anxiety, fatigue, cold, sound and light stimulation, or eating wine, cheese, or coffee, it should be considered to be caused by migraine. Secondly, if the patient has paroxysmal, pins-and-needles pain or electric shock-like pain on one side of the head, it should be considered to be caused by occipital neuralgia. This condition is usually easy to appear during exertion, cold or cold. Thirdly, if the patient has frequent hemiplegic headache, if it lasts for a long time and gradually worsens, it should be considered as the possibility of brain tumor occupancy, which can be clarified by head CT examination. In conclusion, there are more causes of frequent half headache and it is complicated, so it needs to be clarified by combining the nature of headache and related examination.