Photocatalytic　water　splitting　has　been　extensively　studied　in　the　past　decades　and　numerous　semiconductors　have　been　proved　to　be　effective　photocatalysts.　Among　them,　layered　perovskites,　which　comprise　of　a　large　family　of　layered　oxides　with　different　chemical　components,　are　promising　materials　because　of　their　stable　perovskite　slabs　consisting　of　multiple　metal　cations　and　flexible　interlayer　galleries　that　facilitate　modification.　In　this　paper,　we　systematically　review　a　series　of　modified　layered　perovskites　with　enhanced　performance　of　water　splitting.　A　variety　of　methods　have　been　extensively　applied　in　the　modification　of　layered　perovskites.　And　derivate　photocatalysts　with　higher　activity,　better　stability　and　lower　cost　were　obtained.　For　bulk　layered　perovskites,　this　article　introduces　those　that　have　been　modified　via　photocatalyst　design　(ion　doping　and　pillaring)　as　well　as　synthesis　procedure　and　cocatalyst　loading　improvement.　They　show　optimized　chemical　composition,　crystal　structure,　specific　area,　band　energy　and　morphology,　which　have　been　extensively　proved　to　be　key　factors　that　decide　the　performance　of　photocatalysts.　Compared　with　bulk　layered　perovskites,　layered　perovskite　nanosheets,　normally　prepared　by　exfoliation　of　corresponding　bulk　parent　materials,　show　largely　increased　surface　area,　which　is　beneficial　for　charge　transfer.　Further　modification　using　these　nanosheets　as　building　blocks　to　construct　restacked　layered　photocatalysts　with　mono-component　or　multi-components　fully　utilizes　their　ultrathin　and　charged　nature.　The　modified　nanosheets　display　enhanced　charge　separation　and　light　absorption　due　to　designed　band　structure　and　micro-nano　structure,　offering　a　promising　future　direction　of　photocatalyst　design.