The causes of lymph node enlargement are various and can be seen in both infectious and non-infectious diseases. Infectious diseases can be divided into bacterial, viral, fungal, and parasitic infections depending on the pathogen. Non-infectious diseases can be further subdivided into neoplastic diseases and autoimmune diseases. Neoplastic diseases, such as hematologic tumors, lymphomas, and lymph node metastases caused by tumors of some solid organs. If the swollen lymph nodes do not go down, it should be considered from multiple etiologies and combined with the patient’s other symptoms and other examination results, so that a more accurate judgment can be made.