Abstract: In order to study the failure mode and shape optimization of high and steep slope in Weibei open-pit limestone mining area, this paper takes Baoji and Xianyang areas of Weibei as the research areas. Through the collaborative work of remote sensing image, UAV aerial photography technology and field investigation, the characteristics of high and steep limestone slope are summarized, and the failure mode and stability influencing factors of the slope are analyzed. The optimization scheme of slope shape is put forward by using FLAC^3D numerical simulation software through the orthogonal test. The results show that the failure modes of high and steep limestone slopes in Baoji and Xianyang areas are bedding sliding failure, wedge failure and toppling failure; the influencing factors of stability are lithology, rock mass structure and slope shape; the optimal combination of each factor was selected using as few orthogonal test as possible. Finally, the optimization parameter of the 80 meters high slope shape is slope 65°; the step number is 10 and the step width is 4m. This study provides references for the study of failure mode, slope shape optimization and ecological restoration of high and steep slope.