Buns in the ear and fever are most commonly seen in external auditory canal boils, herpetic tympanitis, middle ear mastoiditis, necrotizing otitis externa and so on. 1. External auditory canal boil: due to the hair follicles of the external auditory canal skin and the surrounding tissues of a limited suppurative infection, the germs are mostly Staphylococcus aureus, the early manifestation of local redness, swelling, heat and pain, and then there will be the formation of nodules. 2. Herpetic tympanitis: it is mainly a viral infection that leads to an inflammatory reaction of the tympanic membrane and the skin of the external auditory canal near the tympanic membrane, which will lead to the growth of a bag in the ear and repeatedly cause fever. 3. Mastoiditis of the middle ear: often caused by bacterial infection, which mainly leads to localized swelling and may be accompanied by fever. 4. Necrotizing otitis externa: it is a kind of malignant otitis externa, and the condition is often more serious, which can jeopardize the skull base of the external auditory canal as well as the surrounding soft tissues to become seriously infected, and it can invade the facial nerves, leading to multiple groups of brain nerve damage. Fever in the ear bag, there may be other causes, it is recommended to go to the hospital in a timely manner, to identify the cause of targeted treatment.