The invention discloses a high-performance PBAT plant fiber composite wire material applied to 3D printing. The wire material is prepared from the following raw materials in parts by weight: 70 to 90parts of a PBAT raw material, 5 to 25 parts of plant fiber, 1 to 10 parts of nano filler, 1 to 15 parts of polylactic acid and 0.2 to 1 part of a chain extender. According to the wire material disclosed by the invention, a renewable resource of plant fiber is added into a totally degradable biological material of poly adipic acid/butylenes terephthalate (PBAT) to prepare the composite wire material. Compared with a traditional polylactic acid wire material, the wire material has a lower printing temperature, can prevent the warping problem after printing and has better tensile strength and flexibility; furthermore, the printing appearance of a product is smooth, the printing process of the product is smooth, a printing machine spray head is prevented from being plugged, and the composite wire material is suitable for varieties of 3D forming technologies; in addition, a printed product has natural texture of wood, and the composite wire material has a wide application prospect in the field of 3D printing.