Most of them are secondary to otitis media, otitis externa or mumps, etc. Some inflammatory infections in other parts of the body involve the lymph nodes behind the ear and cause pain behind the ear. This can be detected by routine blood tests and ultrasound examinations. Secondly, some patients with postauricular sebaceous cyst infection may also have pain behind the ear, and cyst-like changes can be detected by clinical ultrasound examination. The third type, patients with mastoiditis and other related diseases, manifesting as redness and pain in the mastoid area behind the ear, occurs in children, but also in adults with low resistance. The fourth type is neuralgia behind the ear. Neuralgia can be caused by fire, can be caused by herpes zoster virus infection in the ear, or can be related to pain caused by inflammation in the throat. All in all, it is recommended to consult the ENT department for a detailed examination and proper treatment of the pain behind the ear.