In　order　to　study　the　effect　of　different　carbon　sources　on　the　phosphorus　release,　PHA　transform,　population　of　the　phosphate　accumulating　organisms　(PAOs),　and　the　anaerobic　stoichiometry　of　PHA　and　glycogen,　three　enhanced　biological　phosphorus　removal　(EBPR)　reactors　were　operated　for　a　long　term　in　the　sequencing　batch　reactor　(SBR)　fed　with　acetate/propionate,　glucose,　or　domestic　wastewater.　The　result　showed　that　three　systems　acquired　stable　phosphorus　removal　efficiency　from　the　182nd　day,　and　FISH　results　showed　that　PAOs　accounted　for　89%±3%,　55%±3%,　45%±4%　of　total　biomass.　Polyhydroxybutyrate　and　polyhydroxyvalerate　were　synthesized　by　PAOs　when　fed　with　acetate,　glucose,　or　domestic　wastewater　as　carbon　source,　only　polyhydroxyvalerate　was　synthesized　when　fed　with　propionate　as　carbon　source,　and　no　poly-3-hydroxy-2-methylvalerate　(PH2MV)　was　detected.　Stoichiometry　research　showed　that　1.15　C-mol　of　PHB　and　0.15　C-mol　of　PHV　were　synthesized　per　C-mol　acetate,　meanwhile　0.47　C-mol　of　glycogen　was　degraded.　0.44　C-mol　of　PHV　was　synthesized　and　0.271　C-mol　of　glycogen　was　degraded　when　fed　with　1　C-mol　propionate.　0.16　C-mol　of　PHV　was　synthesized　and　0.16　C-mol　of　glycogen　was　degraded　when　fed　with　one　C-mol　glucose,　while　very　few　of　PHB　was　synthesized　during　this　process.　The　proportions　of　PHB/COD　and　PHV/COD　were　0.98　and　0.13　respectively　when　fed　with　domestic　wastewater.　Release　of　phosphorus　reached　the　maximum　134　mg·L-1　and　release　rate　was　23.80　mg　P·(g　VSS)-1·h-1　with　acetate　as　sole　carbon　source.　With　propionate　or　glucose　as　carbon　source,　phosphorus　release　rate　was　similar,　while　with　domestic　wastewater　as　carbon　source　phosphorus　release　rate　was　the　smallest.　©　All　Rights　Reserved.