A series of studies on the isolation and structure elucidation of the glycosphingolipids from sea cucumber species have been performed in our laboratory[1][2]. In continuation of the preceding studies on the sea cucumber Pentacta australis, the isolation and characterization of the biologically active glycosphingolipids from the sea cucumber Cucumaria echinata (Gumi in Japanese) has now been conducted in order to develop the novel medicinal resources from marine natural products. Regarding the glycosphingolipid constituents of C. echinata, we have already described the isolation and structure determination of three sphingosine-type glucocerebrosides[1]. In this paper, we report on the isolation and characterization of a further five glucocerebrosides (CE-1-1, CE-1-2, CE-1-3, CE-3-1, and CE-3-2) as well as a ganglioside molecular species (CG-1) from the less polar and polar fractions, respectively, of the chloroform/methanol extract of the whole bodies of C. echinata. The structures of these glycosphingolipids have been determined on the basis of chemical and spectroscopic evidence. The cerebrosides show lethality toward brine shrimps, while the ganglioside CG-1 exhibits neuritogenic activity toward the rat pheochromocytoma cell line, PC-12 cells.