A comparative study with different types of granular activated carbons (GACs) for nitrate removal from water has been carried out. Three important GACs viz. coconut, lignite and wood were selected for the present study. All virgin GACs were treated with zinc chloride (ZnCl2) and carbonized. The optimal conditions were selected by studying the influence of process variables such as chemical weight ratio and activation temperature. Experimental results reveal that chemical weight ratio of 200% and temperature of 500 oC was found to be optimum for the maximum adsorption of nitrate from aqueous solutions. The comparison between virgin and ZnCl2 treated GACs indicate that treatment with ZnCl2 has significantly improved the adsorption efficacy of all GACs, especially the efficiency of coconut GAC has increased up to 6 folds. The adsorption of nitrate on different zinc chloride treated GACs was found in the order: coconut GAC > lignite GAC > wood GAC. The adsorption of nitrate on ZnCl2 treated GACs was studied as a function of contact time and temperature. The kinetic study reveals that equilibrium was achieved within one hour. The adsorption data conform best to the Langmuir isotherm. Results of the present study recommend that adsorption process using ZnCl2 treated coconut GAC might be a promising innovative technology in future for nitrate removal from drinking water.