There are more factors for recurrence of otitis media, mainly as follows: 1. External factors, when swimming, bathing or washing hair, dirty water flows into the ear, which can stimulate the mucous membrane inside the tympanic cavity and lead to recurrence of chronic otitis media. Therefore, patients with chronic otitis media perforation should try to do tympanic membrane repair to isolate the damage and influence of external dirty substances on the middle ear cavity; 2. A few people have recurrence because of the function of the eustachian tube after having surgery, such as respiratory tract infection and poor drainage of the eustachian tube, which leads to recurrence of otitis media; 3. Pre-existing middle ear lesions are not completely cleared, and with the extension of time, such lesions recur again.