BACKGROUND: The quality of Acipenser sinensis deteriorates significantly during frozen storage due to its high water, protein, and unsaturated fatty acid content. Conventional freezing methods are insufficient to preserve it effectively. This study investigated the effects of liquid nitrogen freezing (LNF) on the quality and myofibrillar protein (MP) characteristics of A. sinensis during frozen storage. RESULTS: Freezing A. sinensis with LNF resulted in faster freezing, lower free water content, smaller ice crystals, and less structural damage to MPs than refrigerator freezing (RF). It also resulted in higher shear force, Ca CONCLUSIONS: Liquid nitrogen freezing can maintain the quality of A. sinensis and reduce the degree of MP denaturation and oxidation during frozen storage. Freezing with LNF at -80 °C might be more appropriate for A. sinensis. The study has important implications for the application of cryogenic storage technology to aquatic products. © 2025 Society of Chemical Industry.