Lumps below the ear may be caused by sebaceous cysts, lipomas, enlarged lymph nodes, etc. Patients should consult a doctor in a timely manner to clarify the cause of the disease and then target treatment. 1. Sebaceous cysts: lumps below the base of the ear may be formed by sebum stagnation caused by sebaceous gland blockage in the skin, which is mostly adherent to the skin, and there will be localized redness, swelling and heat pain in the event of infection. 2. Lipoma: a benign tumor composed of mature fat cells, occurring behind the ear can be manifested as a localized lump, and some lipomas may be accompanied by pain. 3. Lymph node enlargement: if the patient has pain in the lump below the root of the ear and there is an infection near the root of the ear or the patient has inflammatory disease of the ear, it should be considered to be caused by lymph node enlargement. If there is a lump below the root of the ear, you need to actively consult a doctor for a systematic examination and a clear diagnosis and standardized treatment.