Some halogenated hydrocarbons and their substituted derivatives are stable compounds and show markedly low chemical reactivity. These properties make them long lasting and non-biodegradable. These compounds are passed on to the aquatic plants and animals by different ways, which are consumed as food by human beings and other animals and become a part of food chain. In the present time, photochemistry is one of the most rapidly expanding and challenging fields for the chemists. The photochemistry of aromatic halo-substituted compounds has been studied with considerable interest in recent years due to the toxic impact of these species on the environment, by developing special techniques for their degradation like UV irradiation, photosensitized sun simulated light irradiation and photo-catalysis. Different categories of halogenated organic compounds have been degraded using the photosensitized reaction and the effect of different parameters affecting the rate of degradation has been studied.