The function of tonsil and indication of tonsillectomy were discussed by many authors for long time. We reported the enzymes in tonsils by preliminary experiment on March ’75 and now, we studied the value of serum enzymes after tonsillectomy to research immunologic and enzymatic function of tonsils and we finally found the changes of it's values in pre- and post tonsillectomized states. The following results were obtained : 1) The values of serum alkaline phosphatase was 2.86 Bessey-Lowry units after tonsillectomy, and 1.82 Bessey-Lowry untis before tonsillectomy, and the values elevated in male and lower aged group than female and high aged group. 2) The values of serum acid phosphatase was 0.42 Bessey-Lowry units after tonsillectomy and 0.22 Bessey-Lowry units before tonsillectomy, and male and female was almostly same values, but the values were almostly higher in high aged group than lower aged group. 3) The values of serum LDH was 247 Berger-Broida units after tonsillectomy and 219 Berger-Broida units before tonsillectomy, and the values were almostly higher in female and lower aged group than male and high aged group.