To　investigate　the　contribution　of　hybrid　fibers　to　the　bending　performance　of　ultra-high　performance　concrete　(UHPC)　slabs,　bending　tests　were　conducted　on　hybrid　fiber-reinforced　UHPC　square　slabs.　Seven　groups　of　square　slab　specimens　(500　mm×500　mm×50　mm)　were　designed:　one　group　containing　only　steel　fibers　(SF),　two　groups　with　SF　mixed　with　macro-polyolefin　fibers　of　two　different　large　aspect　ratios,　two　groups　with　SF　mixed　with　macro-polyvinyl　alcohol　fibers　of　two　different　large　aspect　ratios,　and　two　groups　with　SF　mixed　with　macro-polyethylene　(PET)　fibers　of　two　different　large　aspect　ratios.　The　load-deflection　curves,　initial　cracking　loads,　and　peak　loads　of　each　group　of　specimens　were　measured,　and　the　bending　toughness　indexes　and　energy　dissipation　capacities　were　calculated　and　analyzed.　The　results　indicated　that　the　damage　to　the　slabs　progressed　through　three　stages:　elastic,　strengthening,　and　softening.　The　deformation　curves　of　the　hybrid　fiber-reinforced　UHPC　slabs　exhibited　notable　hardening　characteristics.　Compared　with　slabs　with　only　SF,　the　hybrid　fiber-reinforced　UHPC　slabs　demonstrated　improved　peak　loads　and　bending　toughness　after　cracking.　In　addition,　mixing　coarse　synthetic　fibers　with　larger　aspect　ratios　enhanced　the　mechanical　properties　during　the　strengthening　stage　and　softening　stages　of　the　slabs.　Especially,　the　postcrack　toughness　and　energy　dissipation　capacity　were　significantly　improved.　Furthermore,　the　diameter　of　the　PET　fibers　should　not　exceed　0.　75　mm.　©　2025　Editorial　Board　of　Journal　of　Harbin　Engineering.　All　rights　reserved.