The main factor causing such diseases is fungus, which tends to grow and multiply in a warm and humid environment. When the external ear canal gets water or accumulates a large amount of secretions, as well as in the case of long-term use of antibiotic ear drops, it is susceptible to fungal infections. The principle of treatment is to use topical medication mainly, while paying attention to keeping the external ear canal clean and dry. Before treatment, the secretions should be sent for bacterial culture to clarify the type of infection as a fungal infection. The external ear canal can be cleaned with a boric acid solution to keep the area dry, and antifungal creams, such as Dakin, can be applied locally. If there is a combination of significant systemic disease, such as diabetic immune system disease, the primary disease needs to be treated for the fungal infection of the external auditory canal to be effectively controlled. Only in the case of fungal otitis externa, which is difficult to cure, systemic antifungal drugs are chosen.