Enlargement of one side of tonsil may be caused by peri-tonsillitis, squamous cell carcinoma of tonsil, malignant lymphoma of tonsil and so on, which can be treated with medication, surgery, chemotherapy, radiotherapy, targeted therapy and so on under the guidance of professional doctors. 1. Peri-tonsillitis: If peri-tonsillitis causes enlargement of one side of tonsils, it should be treated with anti-inflammatory, detoxification and antibiotic drugs such as Banlangen granules, Pudilan anti-inflammatory tablets, penicillin and so on, under the guidance of professional doctors. If it is caused by tonsil abscess, but also take surgery for incision and drainage and drainage of pus treatment. 2. Squamous cell carcinoma of tonsil: if squamous cell carcinoma of tonsil causes enlargement of one side of tonsil, the patient should cooperate with professional doctors to take surgery to remove tonsil. If the patient cannot do the surgery, he/she can also choose laser or photodynamic therapy. 3. Malignant lymphoma of tonsil: if malignant lymphoma of tonsil causes swelling of one side of tonsil, chemotherapy, radiotherapy, immunotherapy and biological therapy or combined therapy shall be chosen. If one side of the tonsil is enlarged, it is recommended to go to the local regular hospital as soon as possible for consultation and examination, clear diagnosis of the disease, and follow the medical advice to standardize the use of medication and treatment.