A small hole in the ear with a foul odor is considered to be a symptom associated with an episode of congenital preauricular fistula. Congenital preauricular fistula is a common congenital disorder of the ear caused by embryonic dysplasia or incomplete fusion of the 1st and 2nd parotid arches. A small hole can be seen at the ear screen, and when there is no infection, the patient usually has no symptoms. Once the infection is localized, water or inflammatory stimuli are repeatedly squeezed, resulting in red, swollen, and painful skin at the ear screen, and purulent secretions can be seen when squeezed. In terms of treatment, once the infection has been treated, symptomatic anti-inflammatory treatment is required, with oral anti-inflammatory drugs such as cefixime and amoxicillin, and repeated local wiping with alcohol or iodine volts. If an abscess forms, the first step is to incise and drain it, remove the pus, change the medication locally, and when the inflammation is under control, surgery is required. The fistula, the fistula and the blind end need to be removed together in order to completely avoid recurrence.