Unpleasant　odorous　emitted　from　wastewater　treatment　plants　(WWTPs)　have　been　of　great　concern　for　many　years,　especially　among　local　communities　with　high　population　density.　Knowledge　about　characteristics　of　odorous　gas　release　from　WWTP　can　assist　in　developing　gas　pollution　reduction　technologies.　This　study　investigated　the　emission　and　variation　of　NH3　and　organic　amines　(CH3NH2,　C2H6NH,　and　C3H9N)　at　the　waterair　interface　and　concentrations　of　ambient　air　exposure　from　different　treatment　units　in　a　wastewater　treatment　plant　in　North　China,　which　uses　the　anaerobic/oxic　(A/O)　treatment　process.　Results　demonstrated　that　NH3　and　C2H6NH　emission　fluxes　had　followed　a　descending　order　of　aeration　treatment　units　＞　non　aeration　treatment　units.　NH3　and　C2H6NH　achieved　the　highest　release　concentration　throughout　the　whole　wastewater　treatment　process,　where　0.0023　g　of　NH3　and　0.0018　g　of　C2H6NH　were　emitted　during　the　treatment　of　1　m3　wastewater,　while　CH3NH2　and　C3H9N　had　never　been　detected.　The　emission　of　NH3　and　C2H6NH　from　biological　aeration　tanks　account　for　98　%　and　95　%　of　the　total　discharge　of　wastewater　treatment　plant,　respectively.　The　odor　pollution　of　NH3　and　C2H6NH　in　the　ambient　air　of　different　treatment　units　of　WWTP　was　the　most　serious　in　summer.　At　the　sensory　level,　NH3　dominated　the　malodorous　effect　and　its　exposure　concentration　posed　a　certain　non　carcinogenic　risk　to　workers　in　wastewater　treatment　plant.