Over the last years environmental pollution is considered as serious problem.Halogenate compounds are wide spread pollutants which persistent in marine sediment,underground water and agriculture area.Dehalogenation is only known biodegradation mechanism for certain significant pollutants. It generally makes xenobiotic compounds less toxic and more readily degradable.So far,studies on dehalogenase properties from marine microorganisms were rare and study of this book may shed a light for thoes researcheres who want to get basic information about growth codition for isolate and identify dehalogenase producing bacteria and their properties.