To investigate the stability and deformation response of deep excavation pile-anchor support systems under heavy mobile lifting loads, finite difference software was used to analyze the evolution of displacement fields, pile deformation, anchor cable prestress, and anchor rod axial force in both the excavation and surrounding soils, considering factors such as travel path, load magnitude (200, 400, 600 kN), and loading distance (5, 10, 15 m). The results show that the closer the load is to the excavation, the greater the horizontal displacement and settlement of the support structure and adjacent soils; larger loads lead to greater deformations and a wider range of high shear strain zones. Loading towards the excavation results in a gradual accumulation of displacement and settlement, while loading away from the excavation produces higher initial deformation peaks and more significant residual deformation and prestress loss, with pronounced nonlinear and plastic responses in the support system. Anchor cable prestress drops rapidly as the load approaches, especially in shallow anchors, and the axial force of upper anchor rods increases significantly. Under cyclic loading, the maximum horizontal displacement of the excavation and surrounding soils accumulates with the number of cycles, while settlement increases rapidly at first and then stabilizes. The closer the load is to the excavation, the more significant the cumulative displacement and internal force response, leading to larger deformation and greater prestress loss; when the load distance exceeds 10 m, both deformations and internal force fluctuations are substantially reduced, and under the 15 m condition, all responses are minor, and the excavation remains stable.