Offshore　wind　power　structures　are　subjected　to　complex　dynamic　loads　in　marine　environment　during　their　service.　At　present,　the　real　sea　conditions　can　be　simulated　to　the　maximum　extent　by　the　mixed　test　technology　of　boundary　layer　wind　tunnels,　wave　pools　and　shaking　tables.　However,　due　to　the　high　cost　of　test　and　the　lack　of　a　complete　and　mature　combined　simulation　laboratory　which　can　be　operated　for　wind,　wave　and　seismic　loads,　it　is　difficult　to　carry　out　such　joint　tests.　It　is　advantageous　to　use　self-developed　mechanical　devices　to　simulate　marine　environmental　loads　within　the　controllable　errors　and　which　is　in　simple　operation.　A　series　of　dynamic　model　tests　were　carried　out　on　saturated　sand　foundation　in　order　to　explore　the　feasibility　of　studying　dynamic　response　of　offshore　wind　power　pile　foundations　through　simulating　marine　environmental　loads　by　simplified　methods.　Based　on　Stokes　second-order　wave　theory　and　harmonic　superposition　method,　the　time　history　of　wind,　wave　and　current　load　is　derived　and　programmed,　then　the　wind,　wave　and　current　load　on　offshore　fan　model　structure　is　simulated　by　using　self-developed　complex　dynamic　loading　system.　Finally,　the　dynamic　response　of　single　pile　foundation　in　saturated　sand　under　complex　load　is　analyzed　according　to　the　test　results.　The　test　results　show　that　the　load　displacement　curve　of　single　pile　foundation　in　saturated　sand　is　of　work　hardening　type.　The　maximum　pile　bending　moment　at　the　peak　of　dynamic　load　increases　with　the　increase　of　loading　times,　but　the　cumulative　effect　of　bending　moment　caused　by　the　change　of　load　amplitude　should　be　considered.　The　dynamic　load　in　marine　environment　will　cause　the　increase　of　pore　pressure　around　the　pile,　but　the　increase　of　pore　pressure　on　loading　side　is　not　obvious　in　comparison　to　that　on　the　opposite　side.　The　displacement　change　of　pile　body　is　basically　in　accordance　with　the　fluctuation　trend　of　test　load　and　increases　with　load.　The　cumulative　rate　of　displacement　of　single　pile　decreases　with　the　increase　of　number　of　cycles　under　the　long-term　cyclic　wind　wave　load.　In　this　study,　the　method　combining　theoretical　calculation　of　wind,　wave　and　current　load　with　model　test　of　complex　loading　system　can　consider　the　characteristics　of　dynamic　loads　of　marine　environment　more　accurately,　compared　with　the　empirically　determined　cyclic　load　waveforms　in　conventional　tests,　the　obtained　response　law　is　more　in　accord　with　actual　sea　conditions.