The lymph in the neck is the body’s immune defense, and whenever there is inflammation or germ invasion nearby, its immune function is activated and the lymph nodes become enlarged and can be felt with the hands. More than 95% of the patients with swollen lymph nodes seen in outpatient clinics belong to the above-mentioned condition. Most of them are caused by inflammation of organs near the lymph nodes, such as toothache, laryngitis, etc., or irregular life (staying up late, smoking, eating spicy and irritating foods, etc.). These enlarged lymph nodes are usually isolated, smooth to the touch, and can be pushed back and forth. After the inflammation subsides, most lymph nodes will return to their previous size and cannot be felt on the skin. However, some swollen lymph nodes should not be ignored. Swollen lymph nodes caused by malignant tumors are different from benign lymph node swelling. Oncogenic lymph node enlargement is often not smooth enough to touch and is harder to the touch, even as hard as a stone. It is also not freely pushable like benign lymph node enlargement, and often multiple lymph nodes are connected together in a more fixed position. Generally speaking, there are three types of enlarged lymph nodes that need special attention: 1. painless lymph nodes with a relatively hard texture; 2. enlarged lymph nodes with fever; 3. enlarged lymph nodes with cough or wasting. If the above conditions occur, it may indicate the occurrence of inflammation, tuberculosis or even tumor. For patients with acute lymphadenitis, the main treatment is anti-infection. If there is localized suppuration, the pus should be incised and drained, and the primary focus causing the swollen lymph node infection should be actively treated. In the case of chronic reactive hyperplasia of swollen lymph nodes, no treatment is generally required. When acute infection occurs, the patient can be treated as acute lymphadenitis, and in the case of recurrent attacks, the cause should be carefully searched for and reasonably treated to avoid recurrent attacks. If the enlarged lymph nodes are caused by tuberculosis, the treatment should be mainly systemic treatment, supplemented by local treatment. When drug treatment is unsatisfactory and local excision is possible, surgical treatment can be considered, i.e., tuberculosis lesion removal, and abscess drainage should be incised when septic infection is combined. In case of metastatic cancer of the lymph nodes in the neck or malignant lymphoma, the main treatment is for the primary disease. If thyroid cancer is combined with lymph node metastasis in the neck, radical thyroid cancer surgery should be performed, and lymph node dissection in the central region or lymph node dissection in the lateral cervical region should be performed at the same time.