Abstract: Zhangfeimiao landslide is a large-scale load thrust-type colluvial landslide caused by water storage of the Three Gorges Reservoir. The main treatments included offloading through rock and soil removal, slope toe suppression and anti-slide piles. Based on the research on landslide structure and field monitoring data from 2007 to 2009, this paper analyzes the landslide deformation characteristics before and after treatment and response characteristics of the treatment project to the reservoir water level change. The numerical simulation method was used to analyze relationship between the reservoir water level change and characteristic of the landslide including stress, deformation, stability and the moment of anti-slide piles. The analysis result shows that the landslide deformation is effectively controlled after the implementation of the treatment project. The deformation of the landslide treatment area is significantly smaller than the front of landslide of untreated area under the action of the reservoir water level. The landslide and anti-slide pile are severely affected when the reservoir water level changes from 160 m to 165 m or the water level changes more than 0.6 m/d.