Acetaminophen　(APAP),　a　widely　detected　medical　drug　in　water　environment,　which　might　cause　toxic　effects　to　ecological　environment,　was　selected　to　explore　its　influence　of　high　level　(0.5　and　5.0　mg/L)　on　fixed　biofilm　sequencing　batch　reactor　(FBSBR)　and　aerobic　granule-based　sequencing　batch　reactor　(AGSBR).　The　nitrification　performance　in　FBSBR　was　inhibited　under　the　condition　of　5.0　mg/L　APAP,　but　it　was　not　affected　in　AGSBR.　The　higher　contents　of　extracellular　polymeric　substances,　alginate　like　exopoly　acids　and　sialic　acid　in　AGSBR　made　it　more　stable　than　FBSBR　system　under　the　influence　of　5.0　mg/L　APAP.　90%　of　AGSBR＇s　functional　metabolisms　were　enhanced　after　loading　5.0　mg/L　APAP　and　kept　high　activity.　95.4%　of　APAP　was　removed　in　AGSBR　system　through　adsorption　(7.48%)　and　bio-degradation　(87.92%).　Furthermore,　Pseudoclavibacter,　a　highly　enriched　bacteria　only　in　AGSBR　system　(22%),　might　be　the　potential　APAP　degrading　bacteria,　which　made　APAP　bio-degrade　into　P-aminophenol　and　catechol.　AGSBR　might　have　more　advantageous　than　FBSBR　system　in　treating　pharmaceutical　wastewater　containing　high　level　APAP.