Ten species of echinoderms viz. Holothuria atra, H. scabra, Bahadschia marmorata, Actinocucumls typhus, Pentoceraster regulus, Tropiometra carinata, Astropecten indiciis, Goniodiscaster scaber and Stomopnemtes variolaris have been screened for the biotoxicity of their various organs. Four series of bioassays were carried out. They were tested for toxicity to Chanos and Tilapia fingerlings, toxicity to mice and hemolytic activity. The gradation strongest to weakest toxic species is H. atra (both body wall and viscera), B. marmorata (both body wall and cuvierian tubules), H. spinifera (both body wall and viscera), H. scabra (body wall alone), P. regulus (body wall alone), A. typicus (body wall a lone), A. indicus, H. scabra (viscera), P. regulus (viscera), S. variolaris (viscera), G. scaber, T. carinata and A. typicus. Further detailed analysis is being pursued on isolation and characterisation in order to determine the variation in toxicity and the causative factor responsible for the same.