The invention provides an aluminum alloy refining agent and a preparing technology thereof. The aluminum alloy refining agent comprises, by mass part, 25 parts to 35 parts of sodium chloride, 20 parts to 30 parts of potassium chloride, 5 parts to 10 parts of sodium fluosilicate, 10 parts to 20 parts of sodium fluoride, 5 parts to 10 parts of potassium fluotitanate, 5 parts to 10 parts of potassium fluoborate, 5 parts to 10 parts of sodium carbonate, 10 parts to 20 parts of sodium sulfate, 1 part to 5 parts of potassium nitrate and 2 parts to 5 parts of potassium fluoroaluminate. According to the aluminum alloy refining agent, through the optimized formula, the aluminum alloy refining agent can achieve the aim of refining of deslagging and degassing, the effective grain refining effect is achieved, in the process of deslagging and degassing refining of aluminum alloy melt, the grains are refined, the grains are evenly distributed in the aluminum alloy melt, and therefore the working procedures of intermediate alloy adding and the like in modification of the aluminum alloy melt can be reduced, the production technology of the aluminum alloy is optimized, and the production efficiency of the aluminum alloy is improved.