Abstract: In view of the difficulties in stability analysis and shape design of open-pit mine slope with faults and dip-in weak strata under the condition of horizontal mining and inner row tracing and pressing, taking into account the difference of stratum lithology in the vertical direction of open-pit mine layered slope, service time in the process of engineering development, required stability degree and the three-dimensional effect of deep slope stability, taking the south side of the first mining area of Shengli East No.2 open-pit coal mine as the engineering background, the two-dimensional limit equilibrium method combined with three-dimensional numerical simulation was used to optimize the slope shape of open-pit mine with faults and dip-in weak strata. The research shows that the slope stability of Shengli East No.2 Open-pit Coal Mine is mainly controlled by a series of dip weak layers in the slope, and the fault may serve as the boundary of the sliding body. The potential landslide mode is slicing-bedding sliding or slicing-bedding-bulging failure with circular arc or fault as the side interface and weak layer as the bottom interface. With the increase of tracking distance, the failure mode of slope gradually transits from shallow large-scale failure to deep failure, which is the fundamental reason for the decline of deep slope stability After subsection optimization, the slope should be divided into three stages, the overall slope angle is 14, and the tracking distance between the horizontal mining work side and the inner dump should be 50m.