Abstract: The Mianzhu section of Giant Panda National Park, serving as the core habitat of the Jiuding Mountain giant panda subpopulation, provides essential support for the exchange, dispersal, and long-term scientific monitoring of this population. However, insufficient accessibility and low patrol efficiency in the region hinder daily conservation management and fieldwork. Within the national park, internal route planning must balance multiple objectives. It should provide necessary access for patrol and research activities while avoiding ecologically sensitive areas and minimizing disturbance to habitats. For different types of routes, such as vehicle patrol roads, management and research trails, and ecological recreation trails, it is necessary to establish differentiated suitability assessment criteria and implement tiered development intensity controls. This study develops an integrated technical framework to assess construction suitability and optimize the layout of a multi-level internal road network composed of vehicle patrol roads, patrol and research trails, and ecological recreation trails. By combining the Analytic Hierarchy Process (AHP) and the entropy-weight method, a comprehensive suitability evaluation framework is constructed. The weights of evaluation indicators are determined through the coupling of these two methods, and the spatial distribution patterns of suitability for different road types are mapped. The evaluation indicators are divided into three dimensions: ecological constraints, accessibility and service demand, and comprehensive cost. This achieves a transparent multi-criteria comprehensive evaluation under an ecology-first planning orientation. By directly translating suitability outputs into resistance constraints and constructing resistance surfaces, spatially heterogeneous limitations and preferences are uniformly integrated into cost distance model analysis. Based on the constructed resistance surfaces, this study defines the least-cost paths (LCP) between designated source points as candidate corridors. The minimum spanning tree (MST) is then applied to integrate these candidate corridors into an interconnected backbone network under the requirement of overall connectivity. Furthermore, key road segments are identified and prioritized using edge betweenness centrality, resulting in a phased construction priority list that supports the stepwise implementation of the road system. The results show that ecological indicators dominate the evaluation systems for all three road types, with weights reaching 0.432, 0.642, and 0.717, reflecting the ecology-first orientation. High-suitability areas for vehicle patrol roads, patrol and research trails, and ecological recreation trails are 124.12 km², 73.06 km², and 0.97 km². After optimization, the numbers of retained core corridors for the three road types are 235, 26, and 17. By performing equidistant sampling and integral calculations on the corridors within the resistance surfaces, cumulative resistance costs are derived as indicators representing the comprehensive load of road construction and passage. The cumulative resistance costs for the three road types are reduced by 52.19%, 62.16%, and 54.91%, indicating that lower-cost spatial connectivity is achieved under explicit ecological constraints. By transforming suitability patterns into implementable network design plans and ultimately producing a graded and prioritized corridor list, this study provides technical support for zonal road construction and phased project implementation in the Mianzhu section of Giant Panda National Park. The framework offers a quantitative basis for refined internal road planning and management in the park, as well as methodological reference for protected areas facing similar trade-offs between conservation and access. Future research could incorporate finer-scale habitat quality data and conduct field validation to further enhance the consideration of habitat integrity and improve the assessment of implementation feasibility.