Abstract: Phosphorus (P) is the main limiting factor causing water eutrophication, and its discharge control from wastewater treatment plant (WWTP) is extremely important to reduce natural waterbody pollution. As an economic and sustainable phosphorus removal method, enhanced biological phosphorus removal (EBPR) process has been widely used in WWTPs all over the world. This paper individually reviews the biological P metabolic pathway, related enzymes and functional genes, detection methods of phosphate accumulating organisms (PAOs) abundance and polyphosphate in EBPR process. Furthermore, it highlights the phylogenetic diversity of PAO isolates from EBPR systems during 1980~2021, which is crucial for the control, improvement, and optimization of  EBPR systems. The future research fields on this topic are also proposed.