The method of experiment of acute Pancreatic necrosis of dogs and the classification of experimental cases were same with the described in Chapter I. The measurement of separation percentage of serum protein was performed by the method of solution with Na(2)SO(3) (Yoshikawa-Saito's Method) and by the method of the electrophoretic concentration (Tiselius). The following results were obtained. In the serious group, the decrese of ratio of albumin and globulin and the remarkable increase of the amount of β globulin were observed. On many cases, α and γ globulins decreased but on some of them, α globulin rose again after once it fall down to the lowest level. In the medium and mild groups, ratio of albumin and globulin was markedly decreased, but after one week passed, it bigan to come back to the normal level, however, it improved very gradually. Both of α and γ globulin increased after they had decreased temporarily, but β globulin increased than at the time of the beginning stage of the disease. There was not observed a large difference between values of Na(2)SO(3) method and by Tisolius. In the clinical cases also, the same results as described above were obtained.