The　waste　activated　sludge　(WAS)　coupling　with　denitrification　system　was　built　by　adding　NO2--N　into　WAS　fermentation　system.　The　effects　of　different　temperatures　on　the　system　performance　were　investigated.　The　results　show　that　denitrification　ability　is　relatively　higher　at　35　°C　with　the　specific　denitrification　rate　of　10.6　mg/(g·d).　The　highest　fermentation　performance　is　at　35　°C,　with　the　second　highest　being　at　25　°C,　and　the　lowest　at　55　°C.　The　greatest　sludge　reduction　performance　can　be　obtained　at　35　°C,　and　the　removal　rate　of　VSS　is　up　to　31.5%.