The invention discloses a polypropylene material used for automobile bumpers and a preparation method thereof. The polypropylene material comprises polypropylene, thermoplastic elastomer, inorganic fillers, lubricants, antioxidants, coupling agents, volume stabilizer and light stabilizers. The invention has the preparation method that the inorganic fillers, the lubricants, the chemical inhibitors, the coupling agents, the volume stabilizers and the light stabilizers are added into a mixer for mixing and stirring, then the polypropylene and the thermoplastic elastomer are added into the mixture for mixing and stirring and are added into an extruder to be extruded for molding, so the polypropylene material is obtained. The invention has the advantages of high impact strength, excellent mechanical property, simple and practical preparation process and low cost, is suitable for industrial production and can be used for preparing the automobile bumpers.