Tonsillitis is mainly caused by the following factors: 1. Infectious factors, the main causative agent is group A beta-hemolytic streptococcus, other bacteria also include staphylococcus, streptococcus pneumoniae, and also viruses, such as adenovirus, influenza virus, individual patients are induced by parasites and other related infections. 2. Systemic factors, when the patient’s body resistance and immunity are reduced, the virus invades the tonsil parenchyma and most 3. Infection of the adjacent structures around the tonsils involves the tonsils, commonly associated with acute pharyngitis, acute rhinitis, and cellulitis of the floor of the mouth. Some patients have inflammatory infections such as pneumonia and bronchitis, which also easily induce tonsillitis. 4. Inflammatory infections of the tonsils are easily induced secondary to certain acute infectious diseases, such as scarlet fever, diphtheria, influenza and measles.