The invention discloses a high-fluidity and high-impact ASA material and a preparation method thereof and belongs to the field of polymer composite materials. The ASA material comprises the following raw materials in percentage by weight: 60-80% of an acrylonitrile-styrene copolymer, 20-40% of an acrylonitrile-styrene-acrylate graft copolymer, 2-10% of a compatibilizer, 0.2-1% of an antioxidant and 0.2-2% of a light stabilizer. The ASA material prepared by the preparation method has high impact performance and good processing fluidity, is easy to fill molded large-size abrasive tools and can be widely applied to interior and exterior decorative parts of automobiles and parts of electronic electric appliances.