Luminous bacteria were isolated from marine fishes like sardinella longiceps, those of characterized different species of luminous bacteria such as Vibrio fisheri, V.harveyi, and photobacterium leiognathi. The optimum growths of this species were performed under various growth conditions of different salt (NaCl) concentrations, pH and temperatures. The complex sea water medium exhibit the best result for the growth of luminous bacteria. The 3% NaCl (actual concentration in the medium), 37°C (room temperature), pH – 7.2 (actual medium pH) are optimum conditions for the growth of luminous bacteria. From heavy metal toxicity analysis, it was observed that zinc induces the growth of luminous bacteria where as the cadmium inhibited the growth. Obviously, this investigation has concluded that luminous bacteria act as a biosensor for the detection of heavy metal pollution in marine water.