Nowadays,　the　anaerobic　ammonium　oxidation　(anammox)　process　becomes　a　promising　new　way　of　removing　nitrogen　from　wastewater.　However,　the　performance　of　nitrogen　removal　is　easy　to　be　affected　by　sludge　washout　due　to　the　extremely　long　doubling　time　of　anammox　bacteria　(AnAOB).　As　a　representative　autoinducer　of　quorum　sensing　(QS)　system,　N-acyl-homoserine　lactones　(AHLs)　may　regulate　the　expression　of　certain　genes　involved　in　anammox　reaction.　Previous　researches　have　indicated　that　C6-HSL　and　C8-HSL　(two　types　of　AHLs)　could　stimulate　biofilm　formation.　Therefore,　this　study　mainly　focuses　on　the　effect　of　the　exogenous　autoinducers　(C6-HSL　and　C8-HSL)　on　anammox　performance.　The　results　showed　that　the　growth　of　AnAOB　was　inhibited　at　AHLs　concentration　of　0.5g/L,　however,　the　nitrogen　removal　rate　could　be　enhanced　by　inducing　hzsA　gene　expression　in　the　presence　of　both　C6-HSL　and　C8-HSL.　Moreover,　higher　expression　level　of　hzsA　gene　in　AnAOB　was　induced　by　the　amendment　of　C8-HSL　than　C6-HSL　at　the　same　concentration　level.　©　2018,　Editorial　Board　of　China　Environmental　Science.　All　right　reserved.