The invention discloses a preparation process for an asphalt mixture. The preparation process comprises preparation of basalt fibers, preparation of used tire grains, preparation of broken stones, asphalt heating, preparation of mineral powder and mixing, wherein 25 parts by weight of asphalt, 7 parts by weight of broken stones, 16 parts by weight of used tire grains, 38 parts by weight of basalt fibers and 8 parts by weight of mineral powder are mixed. According to the preparation process, the basalt fibers are added into the asphalt mixture, so that the strength, high temperature resistance and low temperature resistance of the asphalt mixture are improved, a pavement prepared from the asphalt mixture can be prevented from being damaged by the snow-ice weather in the north and exposure to the sun in the south, and is high in flatness, no wheel track is left, and potential safety hazards caused by wheel tracks are eliminated.