The invention discloses a method for preparing agricultural plastic mulching film special for arachis hypogaea from automotive sound-absorbing cotton leftover waste material. Raw materials include theautomotive sound-absorbing cotton leftover waste material, modified starch, arachis hypogaea vine powder, calcium carbonate, polyethylene glycol terephthalate, an ethylene-acrylic copolymer, maleic anhydride, dicumyl peroxide and an auxiliary, wherein the automotive sound-absorbing cotton leftover waste material is used as a main raw material, through starch modification, mixing, compatibility and sound-absorbing material leftover waste material recovery, resource recycling is achieved, energy and material consumption are saved, the problem of three wastes pollution is avoided, the product cost is low, and the agricultural plastic mulching film special for the arachis hypogaea can be degraded in a natural environment, meets a crop growth cycle, is turned into organic waste after being degraded, can be absorbed by soil to improve the plantable property and to promote thriving of an arachis hypogaea seedling stage, and has good economic benefits and social benefits.