Actinomycetes are physiologically very active group of organism producing secondary metabolites of commercial importance. The actinomycetes appeared to have number of characteristics which favor them in competition with other microbes and ensure their survival under unfavorable conditions. The aquatic environment differs from terrestrial environments in several respects. The biological characteristics and distribution of aquatic actinomycetes are expected to be different from those of terrestrial actinomycetes. This book contains introduction , Protocol of isolation of Actinomycetes and Identification using modern techniques.