Using the standard strains of Staph. aureus and Sh. flexneri stocked in the labolatory, the author studied the effect of addition of aureomycin, chloramphenical, Co(++), Mg(++) and Fe(++) on the quantitative changes of RNA, DNA and proteins in the bacteria that was shaken in it's suspension, and also investigated the P(32) incorporations into the nucleic acids and the preteins fractions of these bacteria. The results obtained are following. 1) The amouot of RNA showed marked increase in the bacteria shaken with the addition of glucose into the snspension, whereas that of proteins was found to show only slight increase. The addition of peptone or peptone and glucose into the suspension showed the decrease of the RNA amount, but did the marked increase of the proteins. 2) Aureomycin, chloramphemicol and Co(++) inhibited the increase of the prpteins amount, but Mg(++) and Fe(++) accelerated it. 3) The P(32) incorporations into the nucleic acid and the protein fractions were increased with the addition of peptone, especially in the case of glucose and peptone.