Abstract: Evaluating the stability of mining slope can implement the spatial prediction of slope failures and avoid loss of life and property,Taking 12 influence factors of slope stability into consideration，such as formation lithology，geological structure，weathering and alteration，inclination，exposure，terrain curvature，hydrogeological condition，surface runoff，existing large project，road engineering，vegetation cover and temperature differences，the three kinds of weights (the fuzzy-floor，the most likely value and the fuzzy-ceiling) of each factor are calculated by the improved fuzzy analytic hierarchy processThe geographic database of one mine is built based on ArcGis，and combining with the geological exploration，the spatial analysis module of ArcGis are used to stack the weighted raster layer of various factorsThe overall stability of the research area is evaluated，and different kinds of slope instability have been evaluated by adjusting fuzzy weightThe results show that the southeast and northwest corner in research area is stable，and the unstable area is distributed over the mining area and the bad geological areaHeavy rain and earthquake prediction should be jointly considered to prevent different kinds of instability of landslide，and the reasonable mining method should be chosenIt provides a new thought for evaluating slope stability

Key words: Fuzzy analytic hierarchy process, Slope instability, ArcGis, Stability evaluation