Pain in the root of the left ear is seen for many different reasons. It is common to have swollen lymph nodes around the auricle, especially in the acute phase, with significant pain and even fever. It can be seen in mumps, or oral and maxillofacial infections, where the patient also has significant swelling and pain, fever, and even requires systemic anti-infective treatment. A disease that also commonly occurs in the skin is sebaceous cysts. Since sebaceous glands are abundant around the head and face and the auricle, if the local hygiene is poor or the sebaceous glands do not empty smoothly, obstruction and secondary infection can easily occur, and sebaceous cysts can easily form, and even secondary infection can easily form abscesses, and the patient will have obvious painful symptoms. Local fluctuations will be palpable on examination, and further surgical treatment is required as an option, usually with incision and drainage under local anesthesia, and regular drug changes are required.