Antibiotic　resistance　genes　(ARGs)　and　mobile　genetic　elements　(MGEs)　in　secondary　effluent　from　wastewater　treatment　plants　(WWTPs)　have　a　size-fractionated　character　and　conventional　processes　have　difficulties　in　removing　ARGs　and　MGEs.　Therefore,　this　study　aimed　to　explore　the　removal　efficiency,　removal　mechanism　and　regeneration　potential　of　size-fractionated　ARGs　and　MGEs　by　vacuum　ultraviolet　(VUV)-activated　peroxymonosulfate　(PMS)　and　ascertain　their　potential　hosts　in　secondary　effluent.　The　proportion　of　particle-associated　(PA)-ARGs　and　PA-MGEs　was　85.07　%,　followed　by　free-living　(FL)　fraction　(14.91　%)　and　cell-free　(CF)　fraction　(0.02　%).　More　than　95.00　%∼99.99　%　of　ARGs　and　MGEs　in　PA-　and　CF-　fractions　were　removed　by　VUV/PMS,　but　the　average　removal　efficiency　of　FL-ARGs　and　FL-MGEs　was　66.15　%.　Compared　to　the　regeneration　potential　of　PA-　and　CF-ARGs　and　MGEs　(0.02　＜　C/C0　＜　5.27),　the　regeneration　occurred　mainly　in　FL-ARGs　and　FL-MGEs　(0.08　＜　C/C0　＜　24.06).　·OH　was　the　dominant　radical　(16.810　×　10-6　mol/L)　in　VUV/PMS　for　the　removal　of　size-fractionated　ARGs　and　MGEs　from　the　secondary　effluent,　while　SO4-·　(4.478　×　10-6　mol/L)　played　a　supporting　role　in　the　system　based　on　the　quenching　experiment,　electron　paramagnetic　resonance　spectrometer　and　probe　experiments.　Based　on　full-scale　classification,　conditionally　rare　or　abundant　taxa　(CRAT)　were　the　core　potential　hosts　in　PA-,　FL-　and　CF-　fractions,　while　rare　taxa　(RT)　and　conditionally　rare　taxa　(CRT)　potential　hosts　were　more　diverse　in　the　three　fractions.　This　study　suggests　that　VUV/PMS　can　effectively　remove　size-fractionated　ARGs　and　MGEs　from　secondary　effluent　and　thereby　obviously　reduce　their　dissemination　risk　to　receiving　water　bodies,　providing　technical　support　for　the　engineering　application　of　VUV/PMS　in　full-scale　WWTPs.　©　2024　Elsevier　B.V.