Natural fiber extracted from plants has gained attentions owing to their advantages over synthetic polymers. Nowadays composites from natural fibers are among the most keenly required materials. In the present study raw coir fiber was treated with different nitro compounds in order to enhance the properties of coir fiber. Sample preparation of treated coir fiber was done using annealing method. The purpose of using annealing method is to increase the rate of reaction. Xrd studies revealed that some crystalline compound is present in the newly formed samples. Change in morphology of coir was found when treated with different nitro compounds that are confirmed through SEM technique. The goal of the present study is to show that chemical treatment is an effective method to enhance the properties of coir fiber that may be used as reinforcement in polymers to make ecofriendly, lightweight, biodegradable polymer composites.