Aiming at the limitations of traditional methods for determining the rock movement angle under the geological conditions of steeply inclined multiple ore veins, a comprehensive analysis method based on the critical granular column theory and numerical simulation was proposed. Taking the Shagou stope of Faende mining area in Henan Province as the research object, through engineering analogy, theoretical analysis and numerical simulation, the influence law of the mining of steeply inclined multiple ore veins on the rock movement angle was deeply studied. The nonlinear relationships between rock movement angle and vein distance, vein quantity, as well as dip angle of ore body were revealed, and corresponding empirical formulas were established. The results show that the range of the rock movement angle in the mining area is from 69° to 78°, and the proportion of the height of the critical granular column ranges from 15.8% to 20.7%. By combining the height of the critical granular column with the dynamic correction model of the rock movement angle, the delineation scheme of the safety pillar was optimized, increasing the resource utilization rate to 82.3%. Based on the results of theoretical calculation and engineering practice, a dynamic correction model of the rock movement angle under the coupled action of multiple ore veins was proposed, breaking through the applicable boundary of the traditional analog method for single ore veins, and providing a strong basis for the safe mining of similar complex steeply inclined multiple ore veins.