Contrary to traditional three-way catalysts, high success is obtained in the removal of NOx with selective catalytic reduction catalysts with lean combustion conditions used in the oxygen excess. A zeolite-based catalyst is used commonly to control NOx in selective catalytic reduction applications in lean combustion gasoline engines. In this study, the catalyst was prepared by loading nickel as the reducing agent, over the clinoptilolite type of natural zeolite exposed to various chemical processes, to selectively reduce the nitrogen oxides especially in the lean combustion conditions with the hydrocarbons in the exhaust gas. According to experimental results, the maximum conversion efficiency is 34% for Ni-NZ.