107 echinoderm species occur in the Greek seas, including very rare species recorded just once. At present, they represent 70.4% of the Mediterranean echinodermfauna. The study deals with all the five classes of the phylum: crinoids, 2 species; holothurioids, 34 species; asteroids, 26 species, ophiuroids, 23 species; and echinoids, 22 species.