The　concrete　cap　is　an　important　support　structure　for　stationary　offshore　wind　power,　and　its　construction　efficiency　and　long-term　performance　are　very　important　for　the　healthy　service　of　wind　power　equipment.　Taking　the　4.8　MW　of　the　high-rise　pile　reinforced　concrete　cap　foundation　(RCCF)　in　China　as　a　case　study,　a　novel　composite　concrete　cap　is　proposed　by　using　prefabricated　UHPC　stay-in-place　(USIP)　formwork　in　the　construction　stage,　forming　a　UHPC　composite　concrete　cap　foundation　(UCCF)　in　this　paper.　The　concept　development　of　UCCF,　including　structure　composition,　structure　advantages　and　construction　methods　are　introduced.　On　this　basis,　the　comprehensive　study　of　mechanical　behavior　under　the　ultimate　limit　state　is　analyzed.