Abstract: Rockfalls occur frequently on high-steep hillslopes in the eastern margin of the Tibet Plateau,posing a serious threat to the construction,transport,and maintenance of mountainous transport corridors. The rockfall hazard and risk assessment on Dusi railway and G350 road were analyzed at Shangmujiangping high-steep hillslope,which is a good example to guide rockfall prevention and mitigation in mountain traffic corridors. The orientation information of joints can be acquired from on-site surveys combined with unmanned aerial photography technology,which can reconstruct the high-precision three-dimensional digital surface model of high-steep hillslopes. The failure model and stability of dangerous rockmass of the hillslope are evaluated through stereographic projection. The rockfall trajectory was simulated using 3D rockfall software of RockyFor3D,which can quantitatively and visually assess the rockfall hazard area,hazard zone,and rockfall risk of vehicles on Dusi railway and G350 road. The results show that there are three dangerous rockmass zonings A,B,and C on the scarp of the hillslope,which are controlled by three groups of joints. The failure model of dangerous rockmass is wedge failure associated with slope stability ranging from basically stable to unstable states. The rockfall trajectory is controlled by the terrain of the hillslope,resulting in the maximum bounce height,maximum velocity,and maximum kinetic energy increasing sharply at positions with large descents. The dangerous rockmass zonings A and B do not threaten the Dusi railway and G350 road,whereas they result in a very low hazard level at the northwestern and southwestern edges of the G350 road service area. The rockfall risk of vehicles is located in an acceptable risk zone. The dangerous rockmass zoning C will make the G350 road service area,G350 road,and Dusi railway located in a very low to low hazard level. Therefore,the vehicles on the Dusi railway and G350 road are both located in a risk warning zone,which requires the formulation of corresponding rockfall prevention and mitigation measures in dangerous rockmass zoning C.