The invention discloses a regenerable modified polypropylene material and a preparation method thereof. The regenerable modified polypropylene material comprises the following raw materials in percentage by weight: 57-99.8% of polypropylene, 0-40% of filling agent, 0.03-2% of carbon free radical trapper and 0.1-1.0% of antioxidant. The preparation method comprises the steps of placing the raw materials into a high-speed mixing machine for dry mixing for 3-5min, and further placing into a twin-screw extruder for melt extrusion and granulating. According to the regenerable modified polypropylene material disclosed by the invention, by adding the carbon free radical trapper, due to the unique molecular structure and the high activity of alpha-H, carbon free radicals formed by high-temperature molten polyolefin in a screw cylinder in a hypoxic state can be converted to a stable state and further inactivated, the degradation degree of polyolefin in the extrusion processing process under high-temperature high-shearing condition can be greatly reduced, the original physical and mechanical performances of polyolefin can be retained to the greatest extent, and the modified polypropylene material can be repeatedly put into the market in the form of a conventional material.