[Objective] The regional landscape ecological risks were evaluated, and their spatiotemporal variation was analyzed in order to provide important support for reducing regional ecological risks, maintaining regional ecological security, and promoting regional green development. [Methods] We constructed a landscape ecological risk assessment model based on land use change, and determined the temporal and spatial change characteristics of landscape ecological risk for the Ya’an-Kangding Expressway crossing counties and cities from 2000 to 2020. A geographic detector model with optimized parameters was used to quantitatively analyze the driving factors of landscape ecological risk change. We used the PLUS model to simulate the spatial distribution characteristics and changing trends of landscape ecological risks for the Ya’an-Kangding Expressway passing through counties and cities in 2035. [Results] ① From 2000 to 2020, the main landscape types in the study area were forest land, grassland, and cultivated land, with the fastest growth rate occurring for the impervious surface area (expressway), and the largest increase occurring in forest land area. ② Low and medium landscape ecological risk grades were the main factors. The risk grades spread outward from high to low. ③ Natural factors such as NDVI, elevation, and average annual precipitation were the main driving factors for changes in landscape ecological risk. ④ In 2035, the areas of medium, high, and high risk grades in the study area will decrease under the two different scenarios. The area of significant decline will be particularly obvious under the ecological protection scenario. [Conclusion] The landscape ecological risk levels in the study area were relatively low, mainly low, lower, and medium risk levels, and the ecological environment was gradually improving. The ecological protection scenario was more consistent with the concept of regional sustainable development.