Using Radioactive P(32) as a Tracer, the author studied the effect of bivalent metal-ions and antibiotics on the phosphorus intake of Salmonella 57S, Salmonella 57R, Staphylococcus aureus, and Staphylococcus albus of the departmental stock. And the following results were obtained. 1). It was observed that Mg⁺⁺ and Fe⁺⁺ ions tend to increase the phosphorus intake of these organisms. Therefore these ions should have relation to oxidative phosphorylation. However, it was noticed that Mg⁺⁺ ion had more powerful effect on Salmonella 57S, and Salmanella 57R, contrarily Fe⁺⁺ ion had that on Staphylococcus aureus and Staphylococcus albus. 2). Although aureomycin showed inhibitory effect on the phosphorus intake of the organisms, chloromycetin and penicillin did not show the effect. 3). From the result of phosphorus fractionation, the greater part of P(32) deposit in the cells took in the respiratory state was incorporated in the acid-soluble organic phosphorus faction. 4). Concerning about the effect of aureomycin on the P(32) incorporation in each fractions, it was found strong inhibitory effect of aureomycin on the incorporation of P(32) in the acidsoluble organic phosphorus fraction. But the effect on the incorporation in other fractions could not be observed.