Abstract: To study the influence of quality change of muscle of grass carp (Ctenopharyngodon idellus) on brittleness mechanism of crisp grass carp (C.idellus C.et V) during crisping process, we acquired samples periodically and compared differences in general chemical components, TPA value, muscle protein components, amino acid components and nutritional evaluation. The results show that moisture and fat contents of crisp grass carp were significantly lower than those of grass carp (P < 0.05), while the contents of protein and ash in the former were higher than those in the latter. Besides, the contents of myofibrillar protein, sarcoplasmic protein and stromal protein of crisp grass carp increased by 10.88%, 15.41% and 80.53%, respectively, compared with those of grass carp. Hardness, chewiness, springiness and adhesiveness of crisp grass carp were significantly higher than those of grass carp (P < 0.05). Furthermore, the maximum contents of TAA, total EAA and total UAA of crisp grass carp were 203.5 g·L^-1, 85.6 g·L^-1 and 79.1 g·L^-1, respectively, which were significantly higher than those of grass carp (P < 0.05). The study indicates that the above indices of both crisp grass carp and grass carp experienced changes at different degrees during crisping process, which was important for affecting the changes of brittleness.