The　suction　caisson　can　be　used　in　offshore　wind　farms.　Due　to　the　long-term　horizontal　cyclic　loadings　caused　by　wind,　waves　and　currents,　the　offshore　wind　turbine　foundation　is　required　to　provide　high　horizontal　bearing　capacity　and　limit　the　deflection.　To　better　meet　these　needs,　the　skirted　suction　caisson,　consisting　of　an　internal　caisson　in　an　external　short-skirted　structure,　was　put　forward.　Numerical　studies　were　conducted　with　the　finite　element　software　Z_SOIL　to　investigate　the　cyclic　behavior　of　skirted　suction　caissons　in　sand,　and　the　influence　of　cyclic　load　ratio,　load　eccentricity,　loading　way　and　loading　order　on　the　accumulated　displacement　and　stiffness　were　analyzed.　It　was　found　that　the　soil　stiffness　increases　at　the　small　strain　stage,　the　hardening　small　strain　stiffness　model　was　adopted.　Results　showed　that　the　cyclic　secant　stiffness　does　not　change　significantly　with　the　number　of　cycles　when　the　cyclic　load　ratio　is　less　than　0.5.　However,　it　increases　with　the　increase　of　cycles　when　the　cyclic　load　ratio　is　larger　than　0.5　due　to　the　fact　that　the　sand　around　the　caisson　is　compacted　during　cyclic　loading.　As　the　increase　of　cyclic　load　ratio　and　load　eccentricity,　the　cyclic　secant　stiffness　of　the　skirted　suction　caisson　reduces　linearly,　resulting　in　an　increase　of　both　horizontal　and　vertical　displacement.　It　was　also　found　that　one-way　cyclic　loading　produces　the　largest　horizontal　displacement　while　the　two-way　loading　produces　the　largest　vertical　displacement.　Moreover,　a　decreasing　cyclic　loading　causes　both　the　largest　horizontal　and　vertical　displacement　of　the　caisson,　which　indicates　that　the　previous　cyclic　loading　has　an　important　influence　on　the　bearing　behavior　of　the　caisson.　©　2018,　Editorial　Department　of　Advanced　Engineering　Sciences.　All　right　reserved.