The invention discloses a fire-retardant ASA material and a preparation method thereof. The fire-retardant ASA material is prepared by the following components in accordance with the weight percentage: 72 to 82 percent of ternary graft copolymer which consists of acrylonitrile, styrene, and acrylic ester; 2 to 7 percent of flexibilizer, 12 to 18 percent of tetrabromobisphenol A, 3.0 to 7.0 percent of antimony trioxide, 0.3 to 0.5 percent of UV absorber, 0.1 to 1.0 percent of antioxidant, and 0.3 to 0.7 percent of lubricant. The fire-retardant ASA material not only has good fire-retardant property, but also maintains original toughness and weatherability of the ASA material, and can be widely used in the automotive field, electrical and electronic field, architecture field and other fields, for example, the use in the production of external parts such as automobile exterior mirrors, radiator grilles, tailgates, lampshades and the like, motorcycle panels, camping cars, small hulls, surfboards; all-weather shells such as sewing machines, telephones, kitchen equipment, satellite antennas, and the like; and can also be used in advanced bathrooms, hygiene products, and hot and cold water switches.