Abstract: Saponification conditions of astaxanthin esters from Antarctic krill shells were studied, and effects of pigment concentration, saponification temperature and alkali concentration on saponification were determined by taking free astaxanthin as index. Results showed that when the crude extract concentration was 0.1g/mL, the time and alkali concentration required to complete the saponification were appropriate. The time required to complete the saponification was shorter when the temperature and alkali concentration were higher, but the loss was greater. The most suitable saponification conditions were crude extract concentration 0.1g/mL, saponification temperature 5℃, alkali concentration 0.020mol/L and 55.75μg/mL of free astaxanthin was obtained at 12h of saponification.