The invention belongs to the field of polyurethane elastomers, and particularly relates to a polyurethane elastomer wood-substitute material and a preparation method thereof. The material is prepared from a polymer component and an isocyanato component, wherein the polymer component is prepared from raw materials in percentage by weight as follows: 66%-87% of polypropylene oxide ether polyhydric alcohol, 12.95%-33.95% of a plasticizer, 0.03%-0.05% of a catalyst and 1%-2% of an antifoaming agent; the isocyanato component is prepared from raw materials in percentage by weight as follows: 50%-90% of carbodiimide-modified liquefied MDI, 10%-30% of coarse MDI and 10%-20% of a plasticizer. The obtained polyurethane elastomer wood-substitute material has the advantages that the material has the hardness of wood and is small in thermal deformation, easy to machine, high in machining size accuracy and the like, products are environment-friendly and low in cost, and the material is relatively suitable for production of higher-accuracy products such as molds, gauges, fixtures, jigs and the like. The preparation method of the polyurethane elastomer wood-substitute material is reasonable in process.