This review describes the recent progress in understanding of light harvesting complexes and reaction centers from purple bacteria. Emphasis is paid on the structure of two light harvesting complexes, inner or outer, and the mechanism of the transfer of excited energy among relative pigments (Fig.1). At the same time, it is detailedly stated about the understanding of the structure of the reaction center and the transform mechanism from light energy to chemical energy, usable for life system (Fig.2).