The present publication deals with the different groups of marine organisms namely microorganisms, algae, mangroves, sponges, cnidarians, arthropods bryozoans, molluscs, echinoderms, tunicates, hemichordates, fishes, snakes and mammals producing bioactive natural compounds which will find greater applications in the development of new drugs.This will be the first most comprehensive publication comprising both Pharmacy and Fisheries Science disciplines and it is hoped that this publication will be of great use for not only the students of the courses of the said disciplines at undergraduate and postgraduate levels but also for those disciplines such as .Zoology, Marine Biology, Biotechnology, Lifesciences and Environmental science which have marine biota in their curriculum. Futher, this publication will also be widely welcomed as a valuable reference book by all libraries of colleges and universities.