The invention discloses a regenerated high-activity mineral admixture prepared through resourceful utilization of construction waste and metallurgical waste residue, and a preparation method thereof. The method comprises the following steps: crushing waste concrete so as to obtain cement stone flour; mixing 70 to 98 wt% of cement stone flour, 0 to 25 wt% of metallurgical waste residue and 1 to 5 wt% of floating beads, adding water accounting for 10 to 15% of the total mass of cement stone flour, siliceous metallurgical waste residue and floating beads into the obtained mixture and carrying out drying so as to obtain slag stone flour; calcining the obtained slag stone flour at a temperature of 800 to 1000 DEG C for 15 to 20 min so as to obtain calcined slag stone flour; and mixing 50 to 70 wt% of calcined slag stone flour and 30 to 50 wt% of blast furnace slag powder so as to obtain the regenerated high-activity mineral admixture. According to the invention, solid waste like construction waste, metallurgical waste residue, floating beads and the like is used, so components of the mineral admixture are simple and manufacturing cost is low; and the mineral admixture has high activity and can effectively reduce the amount of cement in preparation of high performance concrete.