Abstract: The preliminary design of a limestone mine has been completed. Because the final slope height of the western slope of the mining area is nearly 200 m，in order to ensure the safety and efficient pro⁃ duction of the mine，it is urgent to carry out in-depth analysis on the stability of the final slope in the west⁃ ern part of the mining area. Through the sampling of rock mass in the mining area and the rock mechanics test，the basic rock mechanics parameters of limestone are obtained. Using the limit equilibrium method， the calculation equation of the stability coefficient of the plane sliding rock slope is derived，and the stabili⁃ ty of the final slope of the limestone mine is systematically analyzed by using the stereographic projection graphic method and ANSYS numerical simulation，and then the safety factor under different final slope an⁃ gles is obtained. Considering the safety and economic benefits of the mining area，it is reasonable to deter⁃ mine the final slope angle of 51°. It is found that the slope stability coefficient obtained by the limit equilibri⁃ um method equation and numerical simulation decreases with the increase of the final slope angle. There⁃ fore，under the premise of ensuring safety，the final slope angle can be appropriately optimized and adjusted to achieve both safety and resource utilization.

Key words: open-pit slope, ANSYS, strength reduction, stability, stereographic projection graphic method