In recent months, I have admitted several patients with first gill slit cysts, which initially manifested as preauricular fistula or pus overflow, and were often misdiagnosed or mistreated, so I would like to talk about the clinical manifestations of first gill slit cysts, and hope that the majority of patients will go to the relevant departments of the relevant hospitals in time to prevent misdiagnosis and mistreatment. Gill slit cysts are caused by the remnants of congenital embryonic development and are classified as first, second, third or fourth gill slit cysts. The most common gill slit cysts are of second gill slit origin; followed by first gill slit origin; third and fourth gill slit origin are less common. The second gill slit cyst, which presents as a lateral swelling in the upper part of the neck, is usually located in the plane below the posterior angle of the mandible mostly at the level of the hyoid bone, near the anterior margin of the upper 1/3 of the sternocleidomastoid muscle. It is sometimes attached to the posterior part of the carotid sheath or protrudes from between the bifurcation of the internal and external carotid arteries towards the lateral wall of the pharynx. The surface of the cyst is smooth, but sometimes lobulated. The size of the mass is variable, the growth is slow, the patient has no conscious symptoms, and if an upper respiratory tract infection occurs it can suddenly increase in size, and then discomfort is felt. If there is a secondary infection, it can be accompanied by pain and radiation to the parotid area. Those occurring above the angle of the jaw and in the parotid area are often of first gill fissure origin; they are called first gill fissure cysts. The first gill fistula or cyst may be accompanied by sebaceous discharge and is easily misdiagnosed as a pre- or post-auricular sebaceous cyst (known as a powder tumor), which is simply removed surgically in the outpatient setting and is prone to recurrence after surgery. The reason for this is that it is often not removed by the inner opening, leaving a stump behind. The internal opening is often at the cartilage and bony connection of the external auditory canal, sometimes closely with the facial nerve trunk, and the facial nerve has to be dissected quite a lot during surgery to prevent damage from causing full-blown paresis (i.e., crooked mouth and eyes), which can seriously affect facial appearance and function (dry cornea causing dry eyes and tearing; crooked corners of the mouth causing air leakage when speaking, salivation when eating, food vestibular groove residue, etc.). If you suspect that the first gill slit cyst should be promptly to the local large point hospital experienced physicians, do not misdiagnosis and mistreatment. I have two cases that were misdiagnosed and mistreated in outside hospitals, resulting in a second surgery that was very difficult to do and easily damaged the facial nerve.