Theecologicalcarryingcapacity,animportantindica-tortoevaluatethesustainabledevelopmentoftheecosystem,meansthepotentialabilityofthenaturalecosystemtocarryso-cioeconomicdevelopmentwhiletheecosystemishealthy.Itislimitedbythecarryingcapacityofnaturalresourcesandenviron-mentandtheelasticityoftheecosystem.Itwillbegreatlysignifi-canttostudytheecologicalcarryingcapacityofHainanProvince,thefirstecologicalprovinceadmittedbytheStateEnvironmentalProtectionAdministrationinChina.Notonlyisthenaturaleco-systemreflected,butalsotheeffectsofhumanactivitiesareem-phasizedbyintegratingtheecosystemhealthanalysisintotheecologicalcarryingcapacityresearch.Theresearchresults,usingtheFactorAnalysistoolsofsoftwareSPSS,indicatethattheeco-logicalcarryingcapacityofHainanProvincefluctuatedobviouslyfrom1996to2005.TheleveloftheecologicalcarryingcapacityofHainanProvincewasrelativelyhighin1996,andreachedintotroughfrom1997to1999.Ithassteadilyascendedtobeabovethemiddlelevelsincethe21stcentury.Theresultsalsoshowthatpolicyfactors,especiallytheimplementationofthe'EcologicalProvince'strategy,wereimportantdrivingforcestoinfluencetheecologicalcarryingcapacity.Withthepopulationrapidlyincreas-ing,thelandandwaterresourcespercapitahavedecreasedquickly.Theamountoftheecologicalcarryingcapacitywaspro-motedremarkablybysocioeconomicdevelopmentespeciallyeconomicgrowthandtechnologyapplications.Allofthesewillprovideusefulsuggestionstoestablishandenactregionaldevel-opmentpolicies,especiallyforprotectingandreconstructingtheecologyandenvironmentofHainanProvince.