The chromatophore from the chemotrophically grown facultative anaerobic photosynthetic bacterium, Rhodopseudomonas gelatinosa ATCC 17013 was isolated through stepwise sucrose gradient centrifugation. The isolated chromatophore showed high activities of the cytochrome $bc_{1}$ complex and cytochrome c oxidase. The activity of cytochrome $bc_{1}$ complex was completely inhibited by .5$mu$M antimycin A,10$mu$</TEX>M myxothiazol, and that of cytochrome c oxidase was completely inhibited by .$50mu$M KCM and $100mu$M $NaN_{3}$but not inhibited by carbon monoxie. The activity of cytochrome c oxidase of th chromatophore was increased by addition of ionophores or protonophores. The reduced-oxidised difference sspectrum of cytochrome $bc_{1}$ complex isolated by affivity chromatography showed the absorption maxima at 553 nm(shoulder at 547 nm), 520 nm, and 418.5 nm, on the other hand, that of cytochrome c oxidase showed .alpha., .betha. and soret peaks at 554 nm, 523 nm, and 421 nm, respectively. The cytochrome c oxidase from chemotrophically grown Rhodopseudomonas gelatinosa seems to be a b-type cytochrome c oxidase.