Low cost adsorbents for the removal of hazardous materials are the critical requirement for the recent environmentalists. In this study, a new activated carbon was prepared from Cotton stalk using phosphoric acid in a Tubular furnace and designated as Cotton Stalk Tubular furnace Carbon (CSTC). Influence of the parameters such as dose of the adsorbent, agitation time, initial concentration of the nitrate solution, pH of the solution and temperature on adsorption of nitrate ions were studied under batch method experiments. Equilibrium data were fitted with Langmuir, Freundlich, Temkin and Dubinin-Raduskevich isotherm equations. Significance of the isotherm constant values was discussed.