The causes of swollen lymph nodes on one side of the parotid area may be: acute lymphadenitis, lymph node tuberculosis, lymphoma, metastasis of malignant tumors, etc. The treatments include anti-infective treatment, anti-tuberculosis treatment, surgical treatment and so on. 1. Acute lymphadenitis: acute lymphadenitis on one side of parotid area is mostly secondary to neighboring infection foci, such as mumps, gingivitis, tonsillitis, etc. The treatment is based on controlling the primary infection foci, and the commonly used medicines are cephalosporin and amoxicillin, etc. When parotid abscess is formed, the treatment may include anti-infective treatment, anti-tuberculosis treatment and surgery. When parotid abscess is formed, local incision and drainage can be performed. 2. Cervical lymph node tuberculosis: cervical lymph node tuberculosis is mainly treated with anti-tuberculosis therapy, commonly used drugs are isoniazid, rifampicin, streptomycin and so on. Larger unfused lymph nodes can also be surgically removed. 3. Lymphoma: the main treatment for lymphoma is chemotherapy, commonly used drugs include doxorubicin, vincristine, platinum drugs, etc. CD20-positive patients can use rituximab, which can improve the remission rate. Patients who are eligible can also undergo hematopoietic stem cell transplantation. 4. Lymph node metastasis of malignant tumors: common malignant tumors that easily metastasize to the lymph nodes of one side of parotid area include thyroid cancer, nasopharyngeal carcinoma, esophageal carcinoma and so on. Treatment is mainly radical surgical resection combined with lymph node dissection, and postoperative chemotherapy, radiotherapy, targeted therapy, etc. will be assisted according to the condition. It is recommended that patients with enlarged lymph nodes in one side of parotid area should go to the hospital as soon as possible, so as to clarify the nature of the lymph nodes as soon as possible and provide targeted treatment. The above drugs should be used according to the doctor’s prescription.