There are 4.5 billion tons of estimated natural zeolites, mainly clinoptilolite, in Turkey. In this study, ammonia adsorption capacity of Gordes clinoptilolite was investigated using bottle adsorption tests. Synthetic water made of ammonium chloride (NH(4)Cl) as ammonia was utilized. The effect of solid concentration, conditioning time, initial ammonia concentration, pH, temperature, and regeneration conditions on the ammonia adsorption was determined and optimum adsorption conditions were established. Adsorption isoterms were fitted to Freundlich and Langmuir models. The regenerated clinoptilolite performs much better than the original one. The mechanism of ammonia adsorption onto zeolite is ascertained. These results indicate that natural clinoptilolite is suitable for the removal of ammonia from waste water.