Marine water samples were collected from a coastal region of Pushpavanam, Nagapattinam District, Tamil Nadu, India. The Physico – Chemical parameters such as Nitrogen, Phosphorus, Calcium, Magnesium, Manganese, Zinc , Copper, Iron, Organic carbon were analyzed using standard methods. Marine samples were subjected to serial dilution and the organisms was counted by measuring plate counting techniques. The isolated marine organisms were grown in suitable medium. In this study, Marine organisms were Pseudomonas aeruginosa, Pseudomonas fluorescens, Bacillus subtilis , Proteus vulgaris, Aspergillus niger, Trichoderma, Streptomyces and Nocardia were identified by cultural, morphological and biochemical characteristics. The identify marine organisms were maintained with suitable broth medium. The molecular weight of the bioactive protein was determined by SDS – PAGE and the bioactive protein produced by marine species was purified using HPLC method. In this study, antibacterial activity was studied using test pathogens were obtained from PG and Research Department of Microbiology , STET Women's College , Mannargudi. The maximum antibacterial and antifungal protein activity was noted in Bacteria, Bacillus subtilis ( 21.5mm) against Escherichia coli, for fungi, Aspergillus niger ( 18mm) against Fusarium. For Actinomycetes, Streptomyces ( 16mm) against Bacillus subtilis. The minimum antibacterial and antifungal protein activity was recorded in Bacteria, Pseudomonas fluorescens ( 12 mm) against Enterobacter aerogenes, for fungi, Trichoderma ( 12 mm) against Penicillium, for Actinomycetes, Nocardia ( 10 mm) against Escherichia coli. Finally, concluded that the isolated marine species such as , Pseudomonas fluorescens, Bacillus subtilis, Aspergillus niger , Trichoderma , Streptomyces and Nocardia were highly recommended to be potential resources of natural antibiotic compounds.