In order to promote the application of recycled aggregate in semi rigid base layers and achieve the resource utilization of construction waste in highway engineering， this article uses equal mass replacement method to systematically analyze the effect of recycled aggregate content (mass fraction) at 0%, 30%, 50%, 70%, and 100% on maximum dry density, optimal moisture content, unconfined compressive strength, and frost resistance of inorganic mixtures, and explains its internal influencing mechanism from a microscopic perspective. The results show that the addition of recycled aggregate reduces the maximum dry density of inorganic mixtures and increases the optimal moisture content. Recycled aggregate can effectively improve the unconfined compressive strength and frost resistance of inorganic mixtures. The best effect is achieved when recycled aggregate content is 70%. At this moment, the unconfined compressive strength of recycled aggregate inorganic mixtures is 4.6 and 6.8 MPa after 7 and 28 d, and the residual compressive strength ratio after 28 and 90 d of freeze-thaw cycles can reach 82.4% and 85.5%.