Three　widely-used　surfactants,　rhamnolipid　(RL),　sophorolipid　(SL)　and　sodium　dodecyl　benzene　sulfonate　(SDBS),　were　chosen　to　investigate　their　effects　on　the　nitrification　systems　treating　step-wised　triclosan　(TCS).　Surfactants　had　little　effects　on　nitrification.　Surfactants　could　promote　the　desorption　of　TCS　and　enhance　the　TCS　biodegradation　in　nitrification　systems.　And　TCS　biodegradation　efficiencies　obtained　with　RL,　SL　and　SDBS　were　1.25,　1.23　and　1.14　times　higher　than　the　control　with　9.0　mg/L　TCS,　respectively.　Illumina　MiSeq　sequencing　showed　that　Amaricoccus　could　be　resistant　to　TCS.　And　Amaricoccus,　detected　with　RL,　SL　and　SDBS,　were　more　abundant　than　the　control.　DNA-based　stable　isotope　probing　assays　revealed　Amaricoccus　was　the　major　TCS　degrader.　And　the　addition　of　surfactants　could　obviously　increase　the　diversity　of　active　TCS　degraders,　especially　for　biosurfactants.　It　seems　that　the　addition　of　surfactants　showed　positive　effects　for　the　nitrification　systems　treating　TCS　wastewater.