The changes of quality, protein composition and volatile flavor compounds of grass carp were studied at 60, 70, 80, 90 and 100 ℃, shape, texture, nutritional value and flavor were set as the evaluation indexes. The results showed that the weight loss rate of fish increased with the treatment temperature, and the L^* value of fish increased, but the a^* value decreased. The hardness, cohesion, amino acid content, E/N ratio showed an upward trend. 87 types of volatile compounds were detected by SPME-GC-MS, including 24 kinds of alkanes, 19 kinds of aldehydes, 14 kinds of acids, 12 kinds of esters, 9 kinds of alcohols, 4 kinds of ketones and 5 other compounds,. Among them, alcohol and aldehydes substances in all samples relative content of were the highest.