Ultra-high　performance　concrete　(UHPC)　is　a　promising　civil　engineering　cementitious　material　characterized　by　superior　mechanical　properties,　where　the　compressive　strength　and　elastic　modulus　are　comparable　to　stone,　therefore,　UHPC　is　an　ideal　potential　rehabilitation　material　for　stone　architecture.　The　excellent　interfacial　bonding　property　is　the　premise　of　UHPC　reinforced　existing　stone　structure.　In　this　study,　the　bonding　behavior　of　interface　between　stone　and　UHPC　made　with　polyoxymethylene　(POM)　fiber　was　investigated　by　push-off　tests,　and　the　influence　of　stone　surface　treatment　on　shearing　performance　was　analyzed　by　experiment　and　numerical　simulation.　The　results　showed　that　the　interfacial　shearing　behavior　of　composites　is　associated　with　the　interface　roughness,　especially　the　groove　treatment,　altering　the　failure　mode　and　improving　the　shear　strength　as　well　as　ductility,　which　is　due　to　the　interlocking　mechanism　and　the　distribution　of　fibers　in　groove.　The　suitable　groove　depth　is　recommended　as　20　mm　in　the　UHPC-stone　composites　using　POM　fiber　with　a　length　of　8　mm.　The　load–strain　relationships　of　UHPC　and　stone　are　similar　in　the　elastic　stage　due　to　the　comparable　elastic　modulus,　while　present　nonlinear　characteristic　in　the　plastic　stage.　The　numerical　simulation　with　a　bilinear　stress-displacement　model　can　effectively　predict　the　interfacial　bonding　behavior　of　UHPC-stone　composites,　and　analyze　the　slippage　distribution　along　with　the　interface.　By　means　of　stress　contour,　it　is　found　that　the　shearing　stress　is　mainly　distributed　non-uniformly　around　the　interface,　and　the　stress　concentration　location　is　consistent　with　the　experimental　failure　region.　Through　the　parametric　study,　it　is　revealed　that　the　interface　shear　capacity　of　UHPC-stone　is　affected　by　the　groove　shapes　and　depths.　©　2023　Elsevier　Ltd