Disclosed are a polyolefin-based resin composition having excellent scratch resistance and low glossiness, a preparation method thereof, and automobile interior and exterior materials fabricated therefrom. The polyolefin-based resin composition comprises about 56 to 97% by weight of a polypropylene block copolymer resin, about 1 to 9% by weight of a thermoplastic elastomer rubber, about 1 to 30% by weight of an inorganic filler, and about 1 to 5% by weight of a fluoroacrylamide-based copolymer based on a total weight of the composition.