The　construction　method　of　bridge　piers　is　usually　cast　in　place　with　steel　formwork　It　is　time-consuming　due　to　affected　by　the　storm　and　formwork　assembling　or　disassembling,　the　construction　progress　is　slow.　A　large　number　of　steel　formwork　and　marine　concrete　lead　to　high　cost　of　bay　bridge.　Even　to　the　extent　that　the　corrosion　resistance　and　impermeability　are　not　ideal.　Ultra-high　performance　concrete　(UHPC)　not　only　has　high　strength,　but　also　has　good　resistance　corrosion　resistance　and　impermeability.　It　can　replace　the　existing　steel　formwork.　Based　on　the　actual　engineering　of　Pingtan　strait　bridge,　use　the　precast　thin　cylinder　of　UHPC　as　the　formwork　then　pour　ordinary　concrete　into　it　to　form　the　UHPC-RC　composite　pier.　Through　the　comparison　of　the　steel　formwork　and　UHPC　formworkformwork　in　the　cost　of　construction,　mechanical　properties　and　durability,　it　can　be　found　that　the　trial　design　pier　has　higher　bearing　capacity,　better　durability　of　the　structure　andlower　cost　which　saves　nearly　30%　compared　to　the　original　design.　The　research　can　provide　reference　for　the　design　of　bay　bridge　in　the　future.