In　order　to　achieve　efficient　removal　of　nitrogen　from　high　ammonia　nitrogen　wastewater　at　room　temperature,　this　study　selected　three　gas　water　ratio　conditions,　8:1,　12:1　and　15:1　respectively.　It　investigated　the　stable　operation　performance　of　partial　nitrification-ANAMMOX　integrated　autotrophic　nitrogen　removal　process　of　biological　aerated　filter　(BAF)　at　room　temperature.　The　results　showed　that　gas　water　ratio　(GWR)　at　the　optimal　operation　time　was　15:1under　the　condition　of　inlet　ammonia　nitrogen　(NH4　+-N)　concentration　of　400mg/L　and　reflux　ratio　of　1:1,　ammonia　nitrogen　removal　rate　(ARE)　was　over　90%,total　nitrogen　(TN)　removal　load　was　1.1kgN/(m3•d),　and　TN　removal　rate　could　reach　83%.　When　the　GWR　is　15:1,the　DO　is　controlled　around　2.41mg/L　and　4.22mg/L,　the　amount　of　NH4　+-N　converted　into　nitrite　(NO2　--N)　in　water　increased,　and　the　ANAMMOX　activity　is　enhanced.　The　real-time　fluorescence　quantitative　PCR　(QPCR)　analysis　of　functional　strains　on　the　biofilm　showed　that　when　the　GWR　was　15:1,　both　ANAMMOX　and　AOB　had　the　highest　abundance,　more　than　1012　copies/g　dry　sludge.　Therefore,　integrated　nitrogen　removal　has　the　best　effect.　At　the　same　time,　studies　have　shown　that　the　ANAMMOX　reaction　is　strengthened　after　increasing　the　gas　water　ratio　and　N2O　is　not　generated　in　the　ANAMMOX　process.　When　the　GWR　is　15:1,　the　total　release　amount　of　N2O　is　the　smallest,　and　the　release　factor　is　0.0012.　©　2019,　Editorial　Board　of　China　Environmental　Science.　All　right　reserved.