Estuaries　are　vulnerable　to　climate　change　and　are　particularly　sensitive　to　extreme　river　discharge　(RD)　and　sealevel　rise　(SLR).　To　understand　the　effects　of　extreme　RD　and　SLR　on　estuaries,　an　integrated　modeling　approach　is　adopted　to　simulate　hydrodynamic　changes　in　the　Yangtze　River　Estuary.　Model　results　showed　that　SLR　will　intensify　the　estuarine　hydrodynamics　in　water　level,　currents,　and　salinity.　Water　level,　current　speed,　and　salinity　increased　linearly　with　the　magnitude　of　SLR.　The　hydrological　model　suggested　a　lower　RD　in　the　future.　This　will　increase　the　saltwater　intrusion,　which　will　be　more　severe　during　the　lower　RD　and　drought　extreme　hydrological　event　(EHE)　conditions.　Model　results　also　suggested　that　the　saltwater　intrusion　is　more　sensitive　to　RD　than　SLR.　In　addition,　the　interplay　between　the　RD　and　SLR　will　exacerbate　the　impacts　of　coastal　oceans　on　estuarine　hydrodynamics,　especially　during　extremely　low　RD　conditions.　Moreover,　the　decrease　of　RD　and　deepening　of　the　channel　due　to　human　activities　will　also　amplify　the　effects　of　SLR　on　the　Estuary,　increasing　the　risk　of　coastal　disasters.