Palatine tonsil is a well recognized tissue as a source of infection and have protectional action, enzyme action, endocrine function and immunological action etc. Especially, among the several actions of the palatine tonsil, the author interested and studied to investigate the immunological action of the palatine tonsil and the following results were obtained : 1. The value and activity of protein and immunoglobulin of human palatine tonsil concern to the role of immune production. 2. Tonsillectomy has not influenced maintain the value of serum protein and immunoglobulin. 3. Clinically, in case of chronic infectious state of tonsil, general symptoms, body weight and systemic diseases are also improved by tonsillectomy.