Abstract: The DEGP family is widely present in cells of both prokaryotes and eukaryotes. In Arabidopsis thaliana, 16 genes coding for DEGP-like proteases have been identified, 4 of which are located in chloroplasts, according to proteomic data. The DEGPs in chloroplas ts of A. thaliana were analyzed by biochemical and molecular biology methods, and results suggested that these DEGPs are involved in the degradation of the photosystem II reaction center protein D1; therefore, they play important roles in the repair cycle and maintenance of the photosystem II complex. In this paper, we review recent progress in res earch into the structure and function of DEGPs in chloroplasts of A. thaliana.