In　order　to　inhibit　the　peak　of　ammonia　nitrogen　(SNH,e)　and　total　nitrogen　(SNtot,e)　concentrations　in　effluent　and　reduce　energy　consumption,　we　present　in　this　paper　a　decision　and　optimization　control　method.　Firstly,　we　establish　the　prediction　models　of　SNH,e　and　SNtot,e　with　neural　network.　Secondly,　we　optimize　the　set　points　of　dissolved　oxygen　concentration　and　nitrate　nitrogen　concentration　with　multiobjective　evolutionary　algorithm.　Lastly,　select　control　strategy　(optimal　control　strategy　or　inhibitory　control　strategy)　based　on　the　outcome　of　prediction　models.　Evaluation　is　carried　out　with　the　Benchmark　Simulation　Model　No.1.　The　results　show　that　the　proposed　method　restrains　the　peaks　of　SNH,e　and　SNtot,e　effectively　while　the　percentages　of　time　of　SNH,e　and　SNtot,e　violations　are　less　than　those　of　the　compared　inhibitory　control　methods,　and　that　the　energy　consumption　using　the　proposed　method　is　less　than　that　using　the　counterpart　inhibitory　control　method　significantly.　Copyright　©　2018　Acta　Automatica　Sinica.　All　rights　reserved.