Abstract: The aim of this study was to investigate the combined effects of CO₂-cold seawater and antioxidants on the quality of Litopenaeus vannamei. Three kinds of antioxidant were dissolved in CO₂-cold seawater respectively,2% 4-hexylresorcinol,2% phytic acid,and 2% lucono delta-lactone. Litopenaeus vannamei was soaked in the mixed solution for 24 h,and then refrigerated at 4℃. The total bacteria count,total volatile basic nitrogen,K-value,polyphenoloxidase activity,sensory evaluation,pH,and texture were determined and compared. The results indicated that the three types of antioxidants all improved the preservation effect of the CO₂-cold seawater and extended the shelf life of Litopenaeus vannamei. After 16 d of storage,the values of total bacteria count,total volatile basic nitrogen,K-value,polyphenoloxidase activity,sensory evaluation,pH,and shear force of shrimps treated by CO₂-cold seawater and 2% phytic acid were 5.78 lg CFU/g,23.26 mg/100 g,60.45%,5.05%,5 point,7.82,9.77 N,respectively. Compared with the treatment of CO₂-cold seawater and 2% lucono delta-lactone on the preservation effects,this treatment had no significant difference (p>0.05). Compared with control group,the shelf life of these experimental groups had prolonged for 2 d,while phytic acid and lucono delta-lactone performed better.