Thesimulationsofnonlinearsloshinginbothtwo-dimensionalandthree-dimensionalliquidtankswithporositygirderarecarriedoutintimedomainbyusingtheMulti-domainBoundaryElementMethod(MBEM).Thecomparisonofthepresentresultsandthereferencesisconductedandshowstheyagreewellwitheachother.Thethree-dimensionaleffectandtheinfluenceofthewidthofliquidtankandtheheightandporosityofthegirderonthenaturalperiodofthemodelarealsodiscussed.