In　order　to　improve　the　phosphorus　removal　effect　in　the　denitrification　and　phosphorus　synchronous　removal　process　by　sulfur/sponge　iron　composite　fillers,　the　phosphorus　removal　effect　by　different　fillers　with　the　coupling　microorganisms　was　studied　to　analyze　the　denitrifying　phosphorus　removal　mechanism　of　the　microbial　coupling　sulfur/sponge　iron　composite　fillers.　The　research　result　showed　that　the　phosphorus　removal　ratio　of　sponge　iron/sulfur　composite　fillers　was　over　95%,　which　was　increased　by　30%　as　compared　to　only　sponge　iron　filler.　In　addition,　the　effluent　TP　concentration　was　reduced　to　less　than　0.1　mg·L-1.　The　analysis　of　X-ray　diffraction(XRD)and　total　iron　concentration　indicated　that　the　main　phosphorus　removal　system　products　which　were　produced　in　the　corrosion　and　phosphorus　removal　process　of　sponge　iron　were　FeOOH,　FeS　and　Fe4　(PO4)3　(OH)3　deposits　and　dissolved　iron　ions;　FeS　and　FeOOH　which　were　the　hydrolysis　products　of　Fe2+　and　Fe3+　converted　PO43-　to　Fe4(PO4)3(OH)3　by　adsorption　and　deposition　so　that　phosphorus　removal　could　be　achieved.　After　the　reactor　of　microbial　coupling　sulfur/sponge　iron　carbon　composite　fillers　became　stable,　the　removal　efficiency　of　TN　and　TP　could　reach　90%　and　more　than　83%,　respectively;　Corrosion　of　sponge　iron　and　phosphorus　removal　process　could　also　be　promoted　by　biological　iron　and　H+　that　was　produced　in　the　sulfur　autotrophic　denitrification　process,　the　system　could　realize　the　combination　of　＇heterotrophic　synergy　autotrophic＇　composite　denitrification　and　chemical　phosphorus　removal,　and　efficient　denitrifying　denitrification　synchronous　phosphorus　removal　process　could　be　achieved　in　the　urban　sewage　treatment　plant.　©　2016,　Science　Press.　All　right　reserved.