Grain refining method for high-entropy alloy

The invention discloses a grain refining method for a high-entropy alloy, and is used for solving the problem that the cost of an existing grain refining method is too high. The grain refining methodfor the high-entropy alloy comprises the steps of placing a high-entropy alloy casting in a lower die, specifically, the high-entropy alloy casting has a recrystallization temperature and a melting point; heating the high-entropy alloy casting to an operating temperature, specifically, the operating temperature is higher than the recrystallization temperature and lower than the melting point; controlling an upper die opposite to the lower die to forge and press the high-entropy alloy casting at a forming speed and a forming pressure, specifically, the forming speed is 0.05-0.1 mm/s, and the forming pressure is 55-60 MPa; and after controlling the upper die to leave the high-entropy alloy casting, rotating the high-entropy alloy casting at a machining angle, forging and pressing the high-entropy alloy casting throu