Piezoelectric　energy　harvesters　(PEHs)　have　attracted　significant　attention　with　the　ability　of　converting　mechanical　energy　into　electrical　energy　and　power　the　self-powered　microelectronic　components.　Generally,　material＇s　superior　energy　harvesting　performance　is　closely　related　to　its　high　transduction　coefficient　(d33×g33),　which　is　dependent　on　higher　piezoelectric　coefficient　d33　and　lower　dielectric　constant　εr　of　materials.　However,　the　high　d33　and　low　εr　are　difficult　to　be　simultaneously　achieved　in　piezoelectric　ceramics.　Herein,　lead　zirconate　titanate　(PZT)　based　piezoelectric　composites　with　vertically　aligned　microchannel　structure　are　constructed　by　phase-inversion　method.　The　polyvinylidene　fluoride　(PVDF)　and　carbon　nanotubes　(CNTs)　are　mixed　as　fillers　to　fabricate　PZT/PVDF&CNTs　composites.　The　unique　structure　and　uniformly　distributed　CNTs　network　enhance　the　polarization　and　thus　improve　the　d33.　The　PVDF　filler　effectively　reduce　the　εr.　As　a　consequence,　the　excellent　piezoelectric　coefficient　(d33　=　595　pC/N)　and　relatively　low　dielectric　constant　(εr　=　1,603)　were　obtained　in　PZT/PVDF&CNTs　composites,　which　generated　an　ultra-high　d33×g33　of　24,942　×　10−15　m2/N.　Therefore,　the　PZT/PVDF&CNTs　piezoelectric　composites　achieve　excellent　energy　harvesting　performance　(output　voltage:　66　V,　short　current:　39.22　μA,　and　power　density:　1.25　μW/mm2).　Our　strategy　effectively　boosts　the　performance　of　piezoelectric-polymer　composites,　which　has　certain　guiding　significance　for　design　of　energy　harvesters.　©　2023　The　Author(s)