Abstract: An immersion solution for quick freezing was using ethanol, propanediol, betaine and sodium chloride.A Box-Behnken experimental design was used to explore optimal immersion solution formulation. The optimal immersion solution was used to study on crisp grass carp, compared the influence of immersion and chilling freezing and traditional-18℃ on the quality changes of crisp grass carp. A freezing point of-66.10℃ was observed for an aqueous immersion solution containing, on a total dipping solution weight basis, 20% ethanol, 10% propanediol, 7% betaine and 10% sodium chloride, respectively. Compared with the other two freezing processing, crisp grass carp frozen in-18℃ had lower content of myofibrillar protein and total-SH, more reduced Ca2+-ATPase activity. The results of physicochemical and textural characteristics indicated that immersion and chilling freezing could assist to reduce the denaturation of fish protein.