Abstract: Landscape ecological impact assessment is an important part of non-pollution ecological and environmental impact assessment, and plays significant role in regional ecological items. Taking the project of controlling desertification in the southern suburb of Datong city from 2002 to 2003 as an example, the landscape ecological impact assessment is conducted based on the 1∶50000 land use map in 2001 and the 1∶10000 project plan map in 2002 and 2003. Regional landscape pattern and landscape ecological before and after the project were compared. Results show that the project can make the landscape more helpful for controlling desertification. The fractal dimension of whole landscape decreases, the status were changed that cultivated land and unused land severely dominate and aggregate, and the landscape diversity was improved; the fractals of cultivated land and forest land were caused to decrease and that of the unused land to increase; fractal dimension of mountainous and semi-mountainous towns were decreased, as well as the contagion and dominance of cultivated land and unused land, and increasing the contagion and dominance of forest land and grassland of these towns were increased.