The invention discloses a completely biodegradable material, and relates to the technical field of high polymer materials. The completely biodegradable material is prepared from, by weight, 55-65 parts of poly-adipic acid / butylene terephthalate, 35-40 parts of polylactic acid, 2-5 parts of polycaprolactone, 0-2 parts of a lubricating agent, 1-4 parts of an antioxidant, 2-5 parts of an auxiliary and 1-4 parts of packing. According to the completely biodegradable material, a formula of a biodegradable material is optimized, a plastic product made of the material obtained by taking the poly-adipic acid / butylene terephthalate as the main raw materials and cooperating with the appropriate polylactic, polycaprolactone and the other auxiliary materials is excellent in comprehensive mechanical performance, the strength is high, the toughness is good, tensile break is not prone to occurrence, the ductility is high, processing is easy, waste materials can be recycled, no polluting emission occurs in the production process, the final product can be completely decomposed into organic matter under the microorganism action, and a nutrient supplementation effect on soil is achieved.