Abstract: The limit equilibrium method(FEM) is used to analyze the deformation rule of loess high slope at Dong Loutian coal mine before and after excavation. The larger displacement of the loess high slope will happen after excavation. The dynamic design method is used for the important protection location according to the displacement development rule and stress concentration region in numerical analysis. The slope surface is supported by anchors and soil nails. The straight arm segment of slope is supported by steel internal bracing and slope protection piles. The simulation results show that the stress field redistributes after excavation and reinforcement and the horizontal displacement of the slope is inhibited effectively. It provides the scientific basis for dynamic design and construction of the important reinforcement region of slope. The design project can be satisfied with the design requirements of engineering safety grade.