Abstract: In the construction of county-level ecological security patterns, different green infrastructure protection modes exert further impacts on the integrity and connectivity of ecological networks by influencing land use evolution. This study establishes four scenarios, namely 'Business as Usual' (BAU), Source Conservation Scenario (SCS), Corridor Conservation Scenario (CCS), and Integrated Source-Corridor Conservation Scenario (ISCCS), to simulate and compare the land use and ecological network responses of Huayuan County in 2035. The results indicate that the impacts of different protection scenarios on land use are mainly manifested in the adjustment of spatial distribution, rather than a significant differentiation in total quantity, and all newly added construction lands avoid ecological spaces to varying degrees. SCS is more conducive to maintaining the integrity of ecological sources, CCS performs better in improving corridor connectivity efficiency and enhancing potential ecological flow transmission, whereas ISCCS does not exhibit a comprehensive connectivity effect that is significantly superior to that of CCS. On this basis, this study proposes an ecological network optimization strategy characterized by 'ecological barrier stabilization, key corridor connection, important node linkage, and zoned and hierarchical management and control', which can provide a reference for the protection of green infrastructure and the optimization of ecological networks in mountainous and hilly counties.