Abstract: To realize three-dimensional visualization and dynamic risk assessment of railway slope hazards, this paper proposed a method for digital twin modeling of railway slopes and spatiotemporal process simulation of dangerous rock and rockfall. This study acquired multi-view images of slopes via UAV oblique photography, constructed a complete slope digital twin, extracted parameters including geometric shape, volume and spatial position of rock masses, analyzed the rolling, bouncing and three-dimensional migration paths of dangerous rocks, and obtained the velocity, bouncing height, impact energy and distribution of accumulation zones for dangerous rock and rockfall to realize the visualization of the whole motion process. This study carried out rockfall simulation tests on the entrance slope of Ludemeng Temple Tunnel on the Xiangyang-Jingmen High-Speed Railway. The results show that the rolling velocity of medium-small dangerous rock and rockfall can reach 12–17 m/s, the maximum bouncing height is about 12 m, and the impact energy ranges from 340 kJ to 8861 kJ. The slope surface morphology and rock mass integrity exert a significant influence on rockfall motion paths and final accumulation positions. The proposed method provides a reliable basis for risk assessment, protection design and operation safety of dangerous rock and rockfall disasters.