In　this　paper,　the　shear　mechanism　of　the　novel　Y-shaped　(Y-S)　connector　encased　in　ultra-high-performance　concrete　(UHPC)　was　analyzed　to　reveal　the　steel-concrete　interface　separation　mechanism　and　the　interaction　mechanism　between　the　connector　and　UHPC.　Subsequently,　a　validated　finite　element　(FE)　model　was　established　for　parametric　analysis　to　investigate　the　effects　of　strength　parameters　and　structural　parameters　on　the　shear　performance　of　the　Y-S　connector,　including　the　yield　strength　of　the　steel　plate　and　penetrating　rebar,　the　compressive　strength　of　the　concrete　and　UHPC,　the　diameter　of　the　penetrating　rebar,　the　effective　width　and　thickness　of　the　steel　plate,　and　the　dimensions　of　the　UHPC　shear　pocket.　The　design　method　for　the　Y-S　connector　was　finally　developed　and　validated,　including　the　improved　shear　capacity　model,　the　shear　stiffness　model,　the　peak　slip　model,　and　the　method　for　calculating　the　load-slip　curves.　The　results　indicate　that　the　UHPC　dowel　in　the　holes　experiences　triaxial　compressive　stress,　and　the　penetrating　rebar　undergoes　deformation　under　the　force　from　the　top　and　bottom　UHPC.　The　yield　strength　of　the　steel　plate,　as　well　as　the　effective　width　and　thickness　of　the　steel　plate,　have　remarkable　effects　on　the　shear　performance　of　the　Y-S　connector　compared　with　other　parameters.　These　analytical　models　can　well　predict　the　shear　performance　of　the　Y-S　connector　in　the　required　precision　range.