The invention relates to recycled concrete and a preparation method thereof, and belongs to the technical field of building material concrete. The recycled concrete is prepared from, by weight, 140-150 parts of cement, 580-590 parts of recycled coarse aggregates, 260-270 parts of recycled fine aggregates, 95-105 parts of machine-made sand, 35-45 parts of river sand, 70-80 parts of mineral additives, 15-32 parts of hybrid fibers, 4.2-4.6 parts of concrete additives and 80-90 parts of water. The preparation method includes the steps: firstly, weighing various raw materials according to formula ratio, and mixing the coarse aggregates, the recycled fine aggregates, the machine-made sand and the river sand; secondly, adding the cement, the mineral additives and the hybrid fibers, uniformly stirring mixture, adding the concrete additives and the water, and uniformly stirring mixture to obtain the recycled concrete. The recycled concrete has the advantages that natural materials are saved, and environmental protection is achieved. The prepared recycled concrete is excellent in working performance and mechanical property, stable in quality and low in cost.