In order to study the spatial and temporal evolution of the regional landscape in Hanjiang River in Shaanxi Province after the construction of hydropower system,remote sensing images of 1988,2000 and 2007 were interpreted and GIS buffer analysis was applied with widths of 500,1 000 and 5 000 m.The results indicated that water areas showed an increasing trend,while the arable land displayed a steady decreasing trend in the study area since 1988.During the sudied period,landscape pattern was in an unbalanced state with frequent two-way conversions,towards the direction that is beneficial for improving the regional ecology.According to the analysis on landscape fragmentation,landscape diversity and landscape shapes,the degree of landscape fragmentation pattern of the study area increased between 1988 and 2000,and the shape became more complex and landscapes was diversified.Between 2000 and 2007,the degree of landscape fragmentation reduced,the shape became more regular and the landscape diversity decreased.These evidences indicated that the landscape pattern experienced a regional ecological improvement.It can be concluded that the hydropower development has exerted great influences on the landscapes in the study area.