Abstract: To address the challenge of supporting high-fill slopes on weak foundations in the mountainous and hilly regions of western China, based on the high-fill project in the Changlinggang area of Baoshan Industrial and Trade Park in Yunnan, this parer proposes a combined support system of anti-slide piles and reinforced earth retaining walls. By analyzing geological survey data and structural interaction mechanisms, along with validation from engineering practices, the study clarifies the synergistic working mechanism in which anti-slide piles provide deep anti-sliding functions while reinforced earth retaining walls offer shallow support and soil improvement. Research shows that this system, through the integration of rigid and fexible structures, effectively resolves deformation control and stability issues of high-fill slopes on weak soil layers. The vertical layered load transfer mode significantly enhances the overall load-bearing capacity. Engineering practice confirms the theoretical rationality and construction feasibility of this solution, providing a new approach for managing high-fill slopes in complex terrains and offering valuable insights for land resource development in western mountainous regions.