The aim of this research was to determine the community structure and saprobic index of plankton in the waters of the Sekanak River, Palembang City and the results of PCA on environmental parameters. The research used purposive sampling method with nine stations. The results found six classes of plankton, namely Ciliata, Bacillariophyceae, Chlorophyceae, Conjugatophyceae, Cyanophycae and Euglen…