Abstract: To systematically evaluate the slope protection effect of different slope protection technologies, by investigating the influence of a large number of slope protection technologies on the ecological environment and slope characteristics along the slope, based on the rough set theory and conditional information entropy, the correlation between slope protection effect and stability, erosion resistance and other factors was analyzed, combined with the importance of the optimal solution optimization evaluation index, an index weight determination method suitable for the slope protection effect of mountainous highways was proposed, and a slope protection effect evaluation system was constructed. Using fuzzy theory and fuzzy comprehensive evaluation theory, a fuzzy comprehensive evaluation method for the protection effect of mountain highway slope was established. Relying on the analysis of 11 common slope protection technologies on a mountainous physical slope, it was obtained that the slope protection effect of ecological concrete protection technology and geonet grass planting protection technology was the best. The combined technology of ecological concrete and geogrid grass planting was simulated and calculated. It was found that the maximum horizontal displacement and maximum shear strain of the slope were reduced by 66.21% and 90.17%, respectively, and the stability coefficient of the slope increased from 1.252 to 1.351, which meet the requirements of the specification. This study provides a new idea for the optimization of slope protection technology for mountain highways.