Effect on serum protein in rabbit irradiated the whole body and the woman irradiated the breast were studied by the paper electrophoretic technique. The rabbits irradiated with X-rays were divided into 2 groups. The first group was irradiated daily with 300 R of X rays for 10 days. The second group was irradiated with 3000 R at a time. The woman group was irradiated daily wtih 300 R of X-rays for 10 days. Data obtained from the present study are summarized as follows:
1) It was found that slight decreases of alubumin fraction and A/G ratio were observed in each group after X-rays irradiation.
2) There were significiant increases of α2- and β-globulin fractions.
3) Abrupt increases of β-lipoprotein fraction and β/α ratio were also observed in the same each group after irradiation