Abstract: Based on the techniques of RS & GIS and methods of landscape ecology, changes in landscape patterns and the driving force in the Eastern Qilian Mountains were analyzed. 1) At the patch level, the research area landscape was a grain grade structure in 1994 and 2008. There were large numbers, but a small area of mini- and small-patches while in contrast, there were few middle-, large- and huge-patches but they occupied a large area. There were great changes in the Eastern Qilian Mountains landscape from 1994 to 2008. The areas of forest, shrub and grassland remained at 78.2%, 66.7% and 86.3% of the original area respectively, and 28.1% of the shrub area came from the forest landscape. Additionally, 4.8% of the original grassland area and 12.7% of the original snow area had degenerated into bare land, and there was a dramatic transformation between forests and shrubs, snow and bare areas. The shape of patches of forest, snow and water became more simple and regularized. 2) The analysis of landscape diversity showed that evenness and fragmentation indexes of the Eastern Qilian Mountains in 2008 increased compared with those in 1994, while landscape dominance and isolation indexes decreased. The overall level of landscape diversity and heterogeneity increased, the dominant role of main plaque control decreased in the landscape which developed towards diversification and homogenization. 3) Natural factors were the main reason for temperature rise and the reduction of snow area, while precipitation increasingly influenced the decline in water area. Human factors, especially excessive logging, was fundamental for the reduction of forest area and for the degradation to shrubland.