The　dynamic　simulation　system　of　the　marine　environment　was　constructed　with　Open　Inventor.　The　platform　was　employed　for　the　construction　of　3D　models　and　the　simulation　of　marine　environment.　The　system　uses　the　data　which　are　acquired　by　underwater　devices　to　build　the　3D　marine　environment.　The　system　can　not　only　meet　the　requirements　of　simulating　the　marine　environments　for　multiple　users,　but　also　allows　users　to　view　the　scenes　of　different　position　or　different　time　according　to　their　own　requirements.　Some　functionalities,　including　play,　pause,　fast-backward,　and　stop,　are　also　well　supported.　The　System　was　tested　in　the　shallow　areas　of　the　South　China　Sea.　The　test　results　show　that　the　system　meets　the　requirements　of　real-time　and　realistic　simulation,　and　achieves　a　good　simulation　result.