Using the typhus bacilli taken from the departmental stock, the author obtained crude nucleoprotein fraction, Julianelle substance and Boivin substance by respective fractionating procedure and investigated the antigenic properties of these fractions with the use of hemolysis test, precipitation test and the inhibition test for hemagglutination in the presence of influenza virus. The following results were obtained. 1) As the result of hemolysis test, crude nucleoprotein fraction showed most favorable antigenic capacity through the fractions obtained from Sal. typhi and Sal. paratyphi A and B, then Boivin substance followed that, but the other fraction had no significance for antigenic capacity. In addition to this, chick's erythrocytes was most favorable for the hemolysis test to carry the sensitivity. 2) By the precipitation test, it was noticed that Julianelle substance, Boivin substance and crude nucleosprotein fraction were avilable respectively as the precipitinogen. Especially, on the study of precipitation test using Julianelle substance and Boivin substance both obtained from various type of Sal. typhi, and antiserum obtained by injection of these substances, it could be supposed the existence of type specificity on antiserum. From old days, the members of Salmonellae were classified depending upon the antigenic properties of agglutination reaction. The author studied the type specificity from the point of precipitation reaction, and noticed fairly evident specificity. 3) As the cellular fractions of bacteria used for the inhibition test of hemagglutination, the author noticed the superiority on crude nucleoprotein fraction or Boivin substance than Julianelle substance, which was reported to be favorable for inhibition. However, these action for inhibition was seemed to be really unspecific, therefore it could be said no type specificity was present at all.