Inflammation of the tonsils may cause headaches, for reasons including inflammatory diseases caused by tonsillitis, and pain radiating to the head, as follows: First, induce inflammatory diseases: inflammation of the tonsils, if not controlled in time, induces inflammatory diseases in the patient’s whole body, which can lead to fever. Once the fever is over, it can lead to sympathetic excitation of the patient’s whole body, producing a large amount of catecholamines that dilate the blood vessels in the head, which can lead to headaches. Second, the pain radiates to the head: when tonsillitis occurs, the patient will experience significant pain in the pharynx, and the more severe the lesion, the heavier the pain will be. This pain can be radiated to the head through the nerves, inducing a headache in the patient. Most of the headaches caused by tonsillitis are the manifestation of the aggravation of the disease, which requires the improvement of routine blood and ENT examinations, and the increase of anti-inflammatory and other symptomatic treatment to avoid further severity of the disease. If tonsillitis is not controlled in individual patients, it may cause intracranial infection, which is of course rare at present, but it is necessary to be vigilant clinically.