Ishigawa(1965) was certain that γ-globulin level in serum of the Wegener's granuloma was increased. More than that of normal person through experiment and Hashimoto(1968) reported the value of serum LDH was increased about 72.9%, Imaii also reported the increment of alkaline phosphatase isoenzyme, in cases of head and neck cancers. The author has been studied the change of serum contents such as γ-globulin, LDH and alkaline phosphatase in cases of head and neck cancers to consider the clinical significance and the pathogenesis as a preliminary study of the cancer, and the following results were obtained : 1) LDH and alkaline phosphatase in serum are 974±149 unit and 2.53±2.275 SU. 2) Total protein is 728±0.57gm/dl and albumin, α₁, α₂, β and γ-globulin are 4.01±0.92gm/dl(55.08%), 0.25±0.066gm/dl(3.43%), 0.68±0.173gm/dl(9.34%), 0.73±0.161gm/dl(10.03%) and 1.61±0.41gm/dl(22.12%). In this study, only γ-globulin level is more increased than that of normal value and the significance for diagnosis of the head and neck cancers would be suspected.