Sore throat for several months may be caused by chronic pharyngitis, chronic tonsillitis, hypopharyngeal cancer, tonsil cancer, laryngeal cancer and so on. 1. Chronic pharyngitis: the symptom of sore throat is commonly seen in acute pharyngitis, which lasts for several months after repeated episodes, resulting in chronic pharyngitis, with dry, itchy and painful throat. 2. Chronic tonsillitis: Chronic tonsillitis is caused by bacterial infection, which leads to enlarged tonsils, sore throat for several months, foreign body sensation and other symptoms. 3. Hypopharyngeal cancer: malignant tumor in hypopharynx stimulates the mucous membrane of pharynx, thus causing persistent sore throat. 4. Tonsillar cancer: the cause is unknown, manifested as enlarged tonsil on one side, ulcerated surface, not smooth, hard to touch, and adhered to the surrounding tissues. 5. Laryngeal cancer: malignant tumor of larynx invades normal tissues of larynx, thus causing the above symptoms, accompanied by irritating cough and other symptoms. It is suggested that patients should go to the hospital in time for systematic examination and diagnosis, and follow the doctor’s instruction to standardize the treatment.