Abstract: According to the fact that GIS can not directly realize the quantitative calculation of slope stability, the application of effective extracting method of data can realize the operation and storage of the attribute value of every grid cell and vector unit based on the strength of GIS support for Python, which can contribute to realize the stability calculation for slope with the design of the script tool based on the residual thrust method and GCSF method. Combined with geological data of the open-pit coal mine, running the script to calculate the stability factor for slope and search the most dangerous sliding surface, and then compared with the numerical calculating results of MIDAS/GTS to verify, the result shows that the stability analysis method for slope based on ArcGIS provides a totally new idea.