The present study is aimed to investigate the impact of arsenic on gill and liver tissues of fresh water fish, Labeo rohita. In the present study, the protein, amino acids, glucose and glycogen were observed in gill and liver tissues of arsenic treated fish. At the arsenic treatment, the level of protein decreased and amino acids increased and glucose increased and glycogen decreased in the gill and liver tissues of fish. The present study concludes that the toxicity of arsenic alters the protein and carbohydrate metabolism of fresh water fish, Labeo rohita.