The invention discloses a preparation method and a use method of cured polymer powder, and relates to the technical field of cured polymer powder. The cured polymer powder is prepared from corn starchand cured polymer powder, does not need maintenance, does not crack or deform, and is naturally formed at the room temperature. The strength can reach 80-90% after 2 to 5 hours at the normal temperature, and reaches 100% after 70 hours. The temperature is high, and the reaction speed is fast. When the outdoor temperature is about 30 DEG C, the polymer powder is uniformly blended according to a ratio and poured into a roadbed, after 3 hours, vehicles can run on the roadbed; the property of the cured polymer powder is opposite to that of Portland cement, the Portland cement shrinks, while the cured polymer powder expands, after the 3D printing building material (the cured polymer powder) is printed and molded, maintenance is not needed, no waste is generated, and according to the construction requirements, different strengths can be achieved; the cured polymer powder is mixed with other materials in proportion, such as aeolian sand, coal ash, sandy soil, slag, stone seeds and the like,the materials are uniformly blended and can be used to repair the damaged asphalt road, sweeping is not needed, the cured polymer powder can be filled into a damaged part, and after 3 hours, the traffic can be recovered.