Fishes are the earliest known vertebrates and flourishes during the Devonian period about 400 million years ago.Fish occupies an important place in an average Indian diet because of its unique qualities. It plays an important role in overcoming the protein-calorie malnutrition which is being faced by the developing countries like. India where about 60% of the population is suffering from protein deficiency. Besides, Fishes also have a rich amount of vitamins mainly A and D which are essential components of a balance diet. The inclusion of fishes in a poor man’s diet is increasing day by day as now it has been established to be the cheapest source of protein for them but on The other hand, their production is hampered because of various environmental pollution hazards. Economically fishes constitute a very important group of animals and provide a rich source of food, liver oil and a number of other by- product like fish meal, fish manure is in glass etc.