The invention discloses a high-performance rare-earth-iron-based giant magnetostrictive material and a preparation method thereof, and belongs to the technical field of magnetic functional materials.The method comprises the following steps that 1, induction smelting is carried out on a (TB1-XMX) fey alloy, M is equal to at least one of Dy, Sm, Ce, Pr, Nd, Ho and Er, X is equal to 0 to 0.70, and Yis equal to 1.75-2.25; 2, the alloy is placed in an inert gas and gradient strong magnetic field environment, and the alloy is at least heated to 150 DEG C above the liquidus temperature, and the temperature is kept for at least 8 minutes; and 3, the rate of 5-120 microns per second is taken, then an alloy liquid is pulled into a liquid metal cooling liquid to achieve directional solidification,and after the temperature of a heating chamber is cooled to the room temperature, the sample is taken out. The prepared magnetostrictive material has the advantages of high mechanical property, the large magnetostriction coefficient and the like; and the method has the advantages that operation is simple, control is accurate, the product performance is excellent, and the high-performance magnetostriction material can be produced in batches.