The　nitrogen　removal　performance　of　simultaneous　partial　nitrification,　anaerobic　ammonium　oxidization　and　denitrification　(SNAD)　biofilm　was　investigated　in　batch　tests.　The　SNAD　biofilm　performed　good　anammox　and　denitrification　activities.　The　NH4+-N,　NO2--N　and　total　inorganic　nitrogen　(TIN)　removal　rates　of　anammox　activity　were　0.121,　0.180　and　0.267kg　N/(kg　VSS·d),　respectively.　The　denitrification　and　nitrite　oxidation　activities　were　0.211　and　0.053kg　NO2--N/(kg　VSS·d),　respectively.　The　suitable　pH　ranges　for　anammox　activity　were　5.0　to　9.0.　The　the　inhibition　effect　of　pH　on　the　anammox　bacteria　could　be　largely　relieved　by　biofilm.　Besides,　the　SNAD　biofilm　was　found　to　perform　high　tolerance　to　the　inhibition　of　NO2--N　and　free　nitrous　acid　(FNA).　The　NH4+-N　removal　rates　for　anammox　process　were　0.087　and　0.029kg　N/(kg　VSS·d)　with　the　NO2--N　concentrations　of　100mg/L　(FNA　concentration　of　70μg/L)　and　150mg/L　(FNA　concentration　of　100μg/L),　respectively.　The　SEM　observations　indicated　that　the　bacteria　in　the　outer　part　of　the　SNAD　biofilm　were　mainly　short　rod-shaped.　In　the　inner　part　of　the　SNAD　biofilm,　the　bacteria　were　mainly　crater-shaped,　which　should　be　anammox　bacteria.　©　2017,　Editorial　Board　of　China　Environmental　Science.　All　right　reserved.