Saltmarsh is a vulnerable and sensitive ecological system which nonetheless provides a valuable ecosystem service for human society.The process of vegetation succession has been increasing recently due to climate changes and human activities.The present work examined spatial and temporal changes in vegetation distribution at the mouth bar in remote sensing images over the past twenty years.Different spatial and temporal dynamics of vegetation community were found.Suaeda salsamarshes was found to have moved from north to south over time and Phragmites australis marshes boundary kept expanding to the south.The succession rate from Suaeda to Phragmites marshes was very fast.Changes in hydrological conditions and terrain elevation was the main driving force for vegetation succession.