The invention discloses a preparation method of frozen crisped grass carp fillets, capable of improving freezing flavor. The preparation method comprises the following steps of: putting regular frozen crisped grass carp fillets in soaking fluid of which the temperature is 10-15 DEG C, and performing soaking, wherein the weight ratio of the frozen crisped grass carp fillets to the soaking fluid is 1 to (2-4), and the soaking fluid contains 10-30% by volume of a purple perilla extracting solution, 5-15% by volume of an abrus mollis extracting solution and 8-12% by mass of table salt; cooking the soaked and preserved frozen crisped grass carp fillets; precooling the cooked frozen crisped grass carp fillets to 4-10 DEG C, and then performing vacuum packing; performing quick freezing on the frozen crisped grass carp fillets after being subjected to vacuum packing; and after the frozen crisped grass carp fillets are frozen, performing frozen storage on the frozen crisped grass carp fillets under the condition of minus 20 DEG C. The frozen crisped grass carp fillets obtained by the method disclosed by the invention have the characteristics of being good in mouth feel, free from freezing flavor, unique in flavor, and convenient to eat.