High　pile　cap　foundation　is　an　important　component　of　the　supporting　structure　system　for　offshore　fixed　wind　power.　Due　to　the　harsh　marine　environmental　conditions,　the　development　of　high　durability　foundation　caps　is　of　great　significance　for　improving　the　long-term　service　performance　of　the　structure.　Ultra　high　performance　concrete　(UHPC)　has　high　strength　and　durability　characteristics,　and　has　superior　application　advantages　in　high-performance　engineering　structures.　This　paper　proposes　a　high　performance　composite　bearing　cap　structure　using　ultra-high　performance　concrete　as　a　membrane　shell　without　disassembly.　The　mechanical　behaviors　and　failure　mechanism　are　analyzed　by　numerical　simulations　under　the　serviceability　limit　state　(SLS)　and　over-design　state　(ODS).　The　results　show　that　the　high　performance　composite　bearing　cap　has　better　mechanical　and　deformation　properties　and　excellent　economic　benefits　compared　with　the　normal　conrete　bearing　cap.