The lymphatic tissue of the neck is derived from the lymphatic drainage of the nose, sinuses, pharynx, larynx, mouth and face, and inflammation or cancer in these areas can invade or metastasize to various groups of lymph nodes in the neck. Sometimes esophageal, chest and even gastrointestinal cancers also metastasize here. Generally, we can identify the nature and cause of the enlarged lymph nodes in the neck according to their location, size, texture, mobility, and the presence or absence of pressure pain, and investigate the possible primary lesions. The common causes are: 1. Inflammation: Acute cases are characterized by redness, pain and heat, with rapid onset and localized pressure pain, and the masses subside after anti-inflammation. Chronic cases have a long duration, are active, have no pressure pain, and are often located in the submandibular region. 2, tuberculosis: can be primary or secondary to the tuberculous lesions in the abdominal cavity, long duration, enlarged lymph nodes in the form of bunches, medium quality, movable, no pressure pain, can be adhered to each other into a group, if caseous necrosis,, ulceration will form a fistula. 3.Metastatic malignant tumor: It is one of the causes of enlarged lymph nodes in the neck, and its primary foci are mostly located in the head and neck, with gradually increasing mass, hard texture, poor mobility, no pressure pain, often one-sided, or bilateral involvement. Nasopharyngeal cancer, tonsil cancer, laryngeal cancer mostly metastasize to supraclavicular lymph nodes, nasal, sinus, mouth and facial cancer often invade submandibular lymph nodes, esophageal cancer metastasize to supraclavicular lymph nodes. 4.Malignant lymphoma: It is a kind of malignant tumor that occurs in the lymphatic reticular tissue. The mass of non-Hodgkin’s lymphoma is painless, progressively enlarging, hard and poorly mobile, while Hodgkin’s lymphoma is mostly bilateral, with fever, hepatosplenomegaly, wasting and weakness symptoms. 5.AIDS: caused by human immunodeficiency virus invasion, long course of the disease, lymph nodes gradually increase in size, often with inguinal lymph node enlargement, fever, emaciation, weakness and leukopenia. Through detailed medical history and careful clinical examination combined with imaging examinations, we will try to find the primary lesion, and when the primary lesion can be found at the end, the nature and cause can be clarified through puncture or biopsy, and then the corresponding anti-inflammatory, anti-TB, surgical resection or radiotherapy treatment can be carried out.