External auditory canal cholesteatoma is an exfoliated epithelial mass containing cholesterol crystals that obstructs the bone of the external auditory canal. It is also known as obstructive keratosis of the external auditory canal. Its histology is the same as that of middle ear cholesteatoma, but it is often mixed with cerumen debris. So, how is cholesteatoma of the external auditory canal treated? The following are the treatment methods for external auditory canal cholesteatoma: 1. If the external auditory canal cholesteatoma invades the mastoid process, it should be treated by mastoid radical surgery or modified mastoid radical surgery. 2. In case of combined infection, attention should be paid to control the infection. However, it is difficult to control the infection quickly, and only after full or partial removal of the cholesteatoma can the inflammation be absorbed. 3.Cholesteatoma without co-infection is easier to remove. It can be removed by using 3% boric acid glycerin or 3%-5% bicarbonate solution (not to be used in case of co-infection) to soften the ear before removal. 4. If the infection is serious and removal is difficult, it can be done under general anesthesia and surgical microscope, and systemic antibiotics should be applied to control the infection. After the operation, the residual or regenerated cholesteatoma should be removed by follow-up observation. 2% salicylic acid ear drops may prevent recurrence.