Theeffectsofwaterdepthonthewave-inducedverticalbendingmomentandshearingforceonaverylargeFPSOarestudiedbyexperimentsandcomputationsforregularandirregularwaves.TherestrictedwaterdepthcompositeGreenfunctionisemployedtodevelopaprogramforthecomputationofthehydrodynamiccoefficientsoftheverylargeFPSOatshallowwater.Athree-segmentmodelwith1:100scaleistestedintheStateKeyLaboratoryofOceanEngineeringatShanghaiJiaoTongUniversityfortheverificationofthenumericalmethod.Theexperimentalandcomputationalresultsshowthatthewaterdepthhasasubstantialeffectonwave-inducedloads.Thewave-inducedverticalloadsincreasewiththedecreaseofwaterdepthforshallowwater.Especially,forultra-shallowwatertheseloadsincreaseveryevidentlywiththedecreaseofwaterdepth.Thelong-termpredictionvaluesofwave-inducedverticalloadsincreasewiththedecreaseoftheratioofwaterdepthtodraught.Thelong-termpredictionvaluesofwave-inducedverticalloadsareabout8％largerthanthosefordeepwaterwhentheratioofwaterdepthtodraughtis3.0.However,waterdepthhardlyaffectsthelongtermpredictionvaluesofwave-inducedloadswhentheratioofwaterdepthtodraughtislargerthan5.0.
