In order to investigate the enzyme activity of L. hebdomadis stock-cultured in author's department, the oxidation of some sugars, carbonic acids and amino acids by the resting organism cultured on vovine serum supplemented Korthof's media was studied. And the results were as follows. 1) It was found that L. hebdomadis was capable of aerobic metabolism as like as L. icterohaemorrhagiae. 2) In the light of sugar metabolism, the organism had the higher enzyme activity to hexose oxidation: but it had remarkably low to pentose oxidation. The oxidative activities on carbonic acids and amino acids was lower than that of true bacteria, though the activity on some substrates, i. e. aspartic acid, glutamic acid, pyruvic acid, succinic acid, and lactic acid, was fairly high. 3) The organism showed the transamination reactions between glutamic acid and aspartic acid, and also between glutamic acid and alanine. 4) Although the author caried out the experiment of additional effect of KCN, NaF, monoiodacetic acid, sodium arsenite, Mg(++) and Fe(++) in order to investigate the metabolic pathway of glucose, it could not establish the metabolic pathway so far as the results obtained.