This study was carried out to investigate nutritional and physiologically active characterizations of sikhae and the seasoned products from the sea squirt Halocynthia roretzi. The total taste values of sikhae fermented for 4 and 5 days were 10.9 and 15.4, respectively, which was lower than for commercially seasoned sea squirts. The sikhaes contained mostly glutamic and aspartic acids. The total amino acid contents of sikhaes fermented for 4 and 5 days were 5.5 and 6.0 g/100 g, respectively, which were lower than those of commercial seasoned-sea squirts or similar. An amount of 100 g of sikhae and its seasoned products contained P, K, Mg and Fe, and these minerals, which are deemed good for our health, were at 10% above the recommended daily requirements. The functional properties of sikhae fermented for 4 and 5 days were as follows: for ACE inhibiting activity, 69 and 69.5%, respectively; for antioxidative activity, 28.9 and 29.3%, respectively; for xanthine oxidase inhibitory activity, 52.8 and 53.1%, respectively; and for α-glucosidase inhibitory activity, 2.4 and 1.4%, respectively. Antimicrobial activity of the 5 day fermented sikhae against Vibrio parahaemolyticus and Staphyloccus aureus was detected in 8 mm and in 7 mm against Escherichia coli.Key words: Ascidian, Halocynthia roretzi, Sea squirt, Sea squirt sikhae, Traditional seafoods 김풍호ㆍ김민지ㆍ김지혜ㆍ이지선ㆍ김기현ㆍ김현정ㆍ전유진ㆍ허민수ㆍ김진수 2 . , (Lee et al., 1993a) (Lee et al., 1994) (Choi et al., 1994;1996) . , , .( Lee et al., 2001). , . , (Kim et al., 1994c;1994d) , (Kim et al., 1994a;1994b)