Enlarged lymph nodes with necrosis are associated with lymphadenitis, tuberculosis and neoplastic diseases. 1. Lymphadenitis: When infected by bacteria and viruses, lymph nodes, which are immune organs, will enlarge to defend themselves against the invasion of bacteria or viruses. If the infection is severe, the enlarged lymph nodes may become necrotic locally or even as a whole. Bacterial infections should be treated with appropriate antibiotics, such as amoxicillin and cefaclor; viral infections should be treated with antiviral drugs, such as ribavirin. 2. Tuberculosis is often caused by Mycobacterium tuberculosis infection. The infested lymph nodes will be enlarged and prone to necrosis. 3. Tumor cells undergo lymphatic metastasis, infiltrate lymphocytes and proliferate and divide in lymphocytes, which will lead to enlarged and necrotic lymph nodes. Pathological biopsy should be performed in time to clarify the nature of the tumor, and surgical treatment should be given, supplemented by radiotherapy. It should be noted that when the lymph nodes are enlarged and necrotic, it is necessary to go to the hospital in time for examination and treatment under the doctor’s guidance.