In order to solve the problem of sharp increase in construction solid waste production and insufficient utilization rate, this paper takes slag-fly ash based geopolymer as inorganic binder, replaces natural gravel with construction solid waste recycled aggregate, and takes urban road base as the target scene to study the mechanical properties of geopolymer stabilized recycled aggregate under different dosage. The results show that with the increase of geopolymer content, the maximum dry density of the mixture increases, the maximum dry density decreases, and the optimum moisture content increases. The unconfined compressive strength of the mixture increases with the increase of geopolymer content and curing age, and decreases with the increase of recycled aggregate content. The variation law of splitting strength and compressive rebound modulus of mixture is similar to that of unconfined compressive strength. It increases with the increase of precursor slag content, geopolymer content and curing age, and decreases with the increase of recycled aggregate content.