To elucidate food value and medicinal effect of sea cucumbers, sugar composition of those gly-coprotein and chondroitin sulfate was studied. The contents of sulfate esters in sea cucumbers were 1.21%(blue), 0.90%(red) and 1.19%(black). Predominant carbohydrates were identified as fucose, glucose, D-mannuronic acid and N-acetylglucosamine, and those amount was more than 80% to total carbo-hydrate, while the minor sugar composition was ribose, mannose, galactose, N-acetylgalactosamine and D-glucuronic acid. Also, the major carbohydrate moiety of glycoproteins of sea cucumbers was revealed as fucose, mannose, N-acetylglucosamine, glucose and ribose, and those amount was more than 86% to total carbohydrate. Galactose, N-acetylgalactosamine, D-glucuronic acid and mannuronic acid were minor carbohydrate moiety. The contents of sulfate esters in glycoproteins were 0.96% for blue sea cucumber, 1.15% for red sea cucumber and 1.13% for black sea cucumber, while those in chondroitin sulfates were 3.52%(blue), 3.60%(red) and 3.72%(black). The carbohydrate moiety of chondroitin sulfate was identified as N-acetylgalactosamine (73~ 87%), fucose (7~15%) and D-glucuronic acid(5~12%). As the base on the IR spectrum of strong absorption appeared in 1240$cm^{-1}$ / for stretching vibrations in S=0 group and weak absorptions in 850$cm^{-1}$ / and 820$cm^{-1}$ /for stretching vibrations in C-0-S group, chondroitin sulfates had sulfate group which was bound to $C_4$in fucose.