Polyvinylidene　fluoride　(PVDF)　hollow　fiber　ultrafiltration　membranes　were　modified　with　carbon　nanotube　(CNT).　Combined　with　the　ozonation　process,　the　effect　of　the　hybrid　pre-ozonation　and　CNT　modification　on　fouling　alleviation　was　investigated.　The　impacts　of　CNT　loading　mass　and　ozone　dosage　on　the　variation　of　flux　and　antifouling　ability　of　the　membrane　modules　were　evaluated.　Under　a　critical　flux　of　144　L•(m2•h)-1,　CNT　loading　mass　of　3　g•m-2,　and　ozone　dosage(O3/DOC)　of　0.22　mg•mg-1,　the　results　revealed　that　the　filtration　volume　of　the　hybrid　process　was　promoted　to　850　L•m-2,　which　was　about　4.5　times　higher　than　that　of　the　original　unmodified　membrane.　With　a　flux　of　18　L•(m2•h)-1　and　15　day　operation,　the　filtration　volume　was　promoted　to　3　000　L•m-2,　which　was　10　times　that　of　the　unmodified　membrane.　The　fouling　membrane　surface　was　observed　using　confocal　laser　scanning　electron　microscopy　(CLSM).　The　results　demonstrated　that　more　living　bacteria　were　present　on　the　membrane　surface　of　the　unmodified　membrane,　which　showed　a　rapid　transmembrane　pressure　(TMP)　increase.　Both　pre-ozonation　and　CNT　modification　decreased　the　total　amount　of　microorganisms　and　the　amount　of　the　living　bacteria　as　well,　which　mitigated　the　increase　in　TMP.　After　pre-ozonation,　the　presence　of　a　CNT　layer　on　the　membrane　surface　further　decreased　the　number　of　living　bacteria.　Although　the　CNT　layer　captured　some　dead　bacteria,　it　had　no　obvious　relationship　with　the　increase　in　TMP.　©　2018,　Science　Press.　All　right　reserved.