Abstract: In view of the low efficiency, poor model fit, and limited practical guidance of traditional slope stability evaluation methods for open-pit coal mines, a new stability evaluation methodology tailored for open-pit coal mine slopes is developed based on the slope stability evaluation project of Baishihu Open-pit Coal Mine. By integrating GIS and FEM technologies with the traditional limit equilibrium method, oblique photography data of the mining area are used to accurately and rapidly generate engineering geological profiles. Two-dimensional limit equilibrium, 2D and 3D finite element numerical calculations are then performed under multiple working conditions, covering four typical scenarios: natural, blasting, seismic, and rainfall. This new method significantly improves the efficiency of open-pit coal mine slope stability evaluation. The constructed 2D and 3D numerical models better conform to the actual mining conditions of the mine, and the resulting safety factors are more practical. Meanwhile, the 3D finite element model compensates for the simplification and one-sidedness of 2D calculations, effectively verifying the accuracy of the 2D results. This integrated approach effectively overcomes the shortcomings of traditional techniques, balancing work efficiency with calculation accuracy, and holds significant engineering application value for enhancing the scientificity and accuracy of slope stability evaluation in open-pit coal mines.