Clinically, the enlargement of lymph nodes in front of the ear is mainly caused by ocular inflammation, ear inflammation and glandular inflammation. 1. Ocular inflammation: for example, acute conjunctivitis, blepharitis, viral conjunctivitis, keratitis, etc. These related inflammations will lead to obvious enlargement of lymph nodes in front of the ear. 2. Ear inflammation: for example, purulent otitis media or acute otitis externa, etc. When these inflammatory diseases spread to the lymph nodes through the lymphatic vessels, they will cause swelling of the lymph nodes in front of the ear. 3. Glandular inflammation: such as mumps, acute tonsillitis, tonsillar abscess, etc., can also lead to swelling of lymph nodes in front of the ear. Because of the relatively large number of factors that can lead to pre-auricular lymph node swelling, it is recommended that patients go to the hospital in a timely manner to clarify the cause of the disease and receive early treatment.