Photoadaptation of Chlorobium (Cb.) phaeobacteroides was investigated under dim and strong light intensity. Absorption spectra of these whole cellIs were different each other. The Soret band intensity and the Qy bandwidth of BChl e in c디l grown under dim light intensity were smaller and more broadened than those under strong light intensity. From HPLC analysis of the pigments, total carotenoid (Car) / bacterochorolphyll (BChl) e ratio of cell increased wi1h increase of light intensities. But camposition of BChl e hamologs almost unchanged. Cb. phaeobacteroides contains 11 kinds of Car including isorenieratene and beta-isorenieratene as major Car. The campositions of Car were different for cells grown under dim and strong light intensities. In conclusion, Cb. phaeobacteroides changes total amount and canposition of Car to adapt various light intensities, while homolog canposition of BChle unchange.