China's Grain for Green Programme (GGP) is the largest ecological restoration programme ever implemented in a developing country, but the ecological effectiveness in its whole implementation region still remain uncertain. Based on the trend analysis of dynamics in ecosystem structure and service, we assessed the ecological effects before and after the implementation of the GGP in 1990–2010 by developing a series of assessment indexes composed of macro-structure, quality, key service of ecosystem and main impacting factors for these changes. Remote sensing interpretation and ecological model simulations based on multisource images are employed. We found that forest land and artificial surface increased slightly while cropland, grassland decreased, with a main transformation of cropland to forest land. The ecosystem quality, including NDVI, vegetation coverage, LAI, vegetation aboveground biomass and NPP, and services of soil retention and sand fixation in the implementation region has been improved. It appeared a warming and drying climate change trend, with a slight increase in human activities.