Abstract: This research aimed to investigate the effects of degree of milling on phenolic profiles, antioxidant activities and flavor components of cooked sea rice. The contents of polyphenols, flavonoids, anthocyanins, and the antioxidant capacity of cooked sea rice were analyzed by Microplate Reader, the flavor components of cooked sea rice were analyzed by HS-SPME combined with GC-MS. The results showed that with the increase of milling time from 0 s to 10, 20, 30, 40 s, the average total phenol content of cooked sea rice decreased by 65.91%, 74.55%, 84.39% and 90.19% The average total flavonoid content decreased by 60.82%, 78.14%, 86.93% and 92.11% The antioxidant capacity of total FRAP antioxidant activity decreased by 67.42%, 73.52%, 85.07% and 91.20% Total ORAC antioxidant activity decreased by 51.61%, 74.16%, 83.48% and 89.16% The volatile compounds content of cooked sea rice decreased by 50.85%, 75.61%, 78.42% and 88.37%. The 2-acetyl-1-pyrroline contributed the most to the flavor of cooked sea rice, and the OAV value decreased by 76.01% after 40 s. Furthermore, sea rice with the same degrees of milling decreased after cooking for total phenols, total flavonoids, total anthocyanins and total FRAP antioxidant activity, total ORAC antioxidant activity. Therefore, the degree of milling should be carefully controlled at 8-10% to improve the balance of sensory quality and retain phenolic profiles, antioxidant activities and volatile compounds during cooked sea rice milling.