The　extracellular　polymeric　substances　(EPS)　of　activated　sludge　are　a　mixture　of　high　molecular　weight　polymers　secreted　by　microorganisms,　which　are　mainly　composed　of　proteins,　polysaccharides　and　humic　substances.　It　is　widely　accepted　that　EPS　have　a　good　adsorption　ability　for　pollutants　with　different　functional　groups.　However,　recent　studies　showed　the　EPS　had　an　inhibitory　effect　on　pollutant　sorption,　which　is　contradictory　to　previous　viewpoint.　Therefore,　in　this　study,　three　types　of　activated　sludge　with　different　EPS　contents　and　compositions　were　used　to　investigate　the　role　of　EPS　in　an　antibiotic-trimethoprim　(TMP)　sorption　process　at　environmentally　relevant　concentration.　The　in　situ　experiments　results　showed　the　adsorption　capacity　of　activated　sludge　for　TMP　were　increased　from　2.98,　5.37　and　28.33　mu　g/g　VSS　to　7.87,　12.93　and　150.24　mu　g/g　VSS　in　nitrifying　activated　sludge,　wastewater　treatment　plant　activated　sludge　and　anaerobic　ammonia-oxidized　activated　sludge,　respectively　after　EPS　extracted.　The　adsorption　process　can　be　well　described　by　the　pseudo-second-order　kinetic　model.　Results　of　zeta　potential,　contact　angles　and　infrared　spectrum　showed　TMP　replacing　proteins　embedded　into　the　cell　membrane　enhancing　the　TMP　adsorption　capacity　of　activated　sludge　after　EPS　extraction.　Our　results　demonstrated　that　less　proteins　in　EPS　of　activated　sludge　is　more　beneficial　for　TMP　adsorption　removal.　(C)　2021　Elsevier　Ltd.　All　rights　reserved.