There　are　overlying　soft　soil　layers　in　most　offshore　sites　of　China,　which　is　disadvantageous　to　the　construction　of　offshore　wind　farms.　To　investigate　the　effect　of　overlying　soft　clay　on　the　bearing　characteristics　of　pile-bucket　composite　foundation　for　offshore　wind　turbines,　we　established　numerical　analysis　models　for　pile-bucket　composite　foundation　in　the　overlying　soft　clay　with　different　thicknesses.　The　bearing　characteristics　were　analyzed　under　unidirectional　loading　(V,　H,　M)　and　combined　loading　(H-M)　by　using　finite　element　software　ABAQUS.　The　influences　of　the　thickness　of　overlying　soft　clay　on　the　ultimate　bearing　capacity　in　all　directions,　the　bearing　capacity　sharing　ratio　of　different　structures　of　pile-bucket　composite　foundation,　and　the　initial　stiffness　kinit　were　studied.　Results　show　that　the　ultimate　bearing　capacity　of　pile-bucket　composite　foundation　in　all　directions　gradually　decreased　with　the　increase　in　the　thickness　of　overlying　soft　clay.　When　the　thickness　of　overlying　soft　clay　was　6　m　(equal　to　the　inserted　depth　of　bucket　penetration),　the　vertical　ultimate　bearing　capacity　of　pile-bucket　composite　foundation　was　reduced　by　12.　86%,　the　horizontal　ultimate　bearing　capacity　was　reduced　by　46.　55%,　and　the　ultimate　moment　capacity　was　reduced　by　34.　86%　.　The　initial　stiffness　kinit　of　pile-bucket　composite　foundation　decreased　with　the　increase　in　the　thickness　of　the　overlying　soft　clay.　In　summary,　the　effect　of　the　overlying　soft　clay　on　the　bearing　characteristics　of　pile-bucket　composite　foundation　should　be　taken　into　consideration　in　the　design　of　foundations　for　offshore　wind　turbines.　©　2023　Harbin　Institute　of　Technology.　All　rights　reserved.