Abstract: Due to the advantages of good production conditions, low cost, large scale and high resource recovery rate, open-pit mining provides important support for mineral resources extraction and national economic development. It is widely used under suitable geological conditions. However, due to the unique topographic structure of mining slope, damage and deformation are prone to occur under the disturbance of mining. It is mainly reflected in macroscopic and microscopic. Macroscopic damage is visually visible and easy to identify due to the large scale and other reasons, while microscopic damage is not easy to be quickly captured. When a large number of microscopic damage is gathered, it will bring great security risks to open-pit mining and seriously restrict the efficient recovery of resources. In view of this, based on the geological occurrence and production technical conditions of a mine, this paper comprehensively uses indoor mechanical test, physical and numerical simulation and field measurement to study the damage, deformation and stability of mining slope under open-pit mining, and reveals the relationship between the fine and microscopic failure laws of rock strata and the damage and deformation of mining slope. The induced mechanism and corresponding law between mining disturbance and crack breeding and expansion of mining slope are defined. It is obtained that the main failure areas of slope affected by mining are located at 1555 and 1565 flat plates, among which the deformation values of 1555 flat plates obtained by physical and numerical simulation and field measurement are 1.170 m, 1.416 m and 1.389 m, respectively, with small difference. It can be verified by each other, and its failure characteristics are slip-pull fracture type, which forms a full-cycle stability evaluation system of mining slope, and provides a basis for realizing safe and efficient production of open-pit mine.