Offshore　wind　turbines　experience　environmental　loads　such　as　winds　and　waves　throughout　their　operational　lifespan,　as　well　as　accidental　earthquakes　in　earthquake-prone　regions.　Earthquakes　typically　include　high-frequency　components　in　the　vertical　direction,　which　can　be　close　to　the　natural　frequency　of　offshore　wind　turbines.　This　study　aims　to　assess　the　impact　of　the　vertical　seismic　component　on　the　dynamic　response　of　monopile　offshore　wind　turbines.　A　three-dimensional　fully　coupled　finite　element　model　is　developed　to　realistically　consider　the　dynamic　interaction　between　the　actual　site　and　the　structure.　The　method　for　simulating　the　interaction　between　water　and　soil　is　incorporated　into　the　numerical　model.　Stochastic　theory　is　utilized　to　simulate　wind　and　wave.　The　model＇s　accuracy　is　validated　by　comparing　numerical　predictions　with　centrifuge　experimental　results.　The　results　of　the　parameters　analysis　indicate　that　the　vertical　seismic　component　significantly　impacts　the　seismic　response　of　offshore　wind　turbines　and　induces　complex　nonlinear　behavior　in　sandy　soil.　©　2024　Elsevier　Ltd