Effect　of　added　carbon　source　and　nitrate　concentration　on　the　denitrifying　phosphorus　removal　by　DPB　sludge　was　systematically　studied　using　batch　experiments,　at　the　same　time　the　variation　of　ORP　was　investigated.　Results　showed　that　the　denitrifying　and　phosphorus　uptake　rate　in　anoxic　phase　increased　with　the　high　initial　anaerobic　carbon　source　addition.　However　once　the　initial　COD　concentration　reached　a　certain　level,　which　was　in　excess　to　the　PHB　saturation　of　poly-P　bacteria,　residual　COD　carried　over　to　anoxic　phase　inhibited　the　subsequent　denitrifying　phosphorus　uptake.　Simultaneously,　phosphate　uptake　continued　until　all　nitrate　was　removed,　following　a　slow　endogenous　release　of　phosphate.　High　nitrate　concentration　in　anoxic　phase　increased　the　initial　denitrifying　phosphorus　rate.　Once　the　nitrate　was　exhausted,　phosphate　uptake　changed　to　release.　Moreover,　the　time　of　this　turning　point　occurred　later　with　the　higher　nitrate　addition.　On　the　other　hand,　through　on-line　monitoring　the　variation　of　the　ORP　with　different　initial　COD　concentration,　it　was　found　ORP　could　be　used　as　a　control　parameter　for　phosphorus　release,　but　it　is　impossible　to　utilize　ORP　for　controlling　the　denitrificaion　and　anoxic　phosphorus　uptake　operations.