Introduction: There are various methods for NO_x abatement from flue gas among which the catalytic methods are more conventional. SCR-NO_x (Selective catalytic reduction of NO_x) is one of the catalytic methods. In this research for the first time, natural clinoptilolite zeolite was used in order to the NO_x abatement using methane as reducing agent.

Materials & methods: The chemical modification of the zeolite is conducted by ion-exchange and calcination methods. The catalytic behavior of the sample was investigated using the integral fixed bed catalytic reactor in flow rate of 400 ml/min at temperature range of 200-500°C.

Findings: The protonated Iranian clinoptilolite zeolite showed a promising performance for NO_x reduction via selective catalytic reduction by Methane. The corresponding temperature of maximum activity (63% conversion of NO_x to N₂) was 450 °C at a low GHSV of 20,280 h^-1.

Discussion & Conclusion: The results showed that this zeolite and its preparation method is an effective method for NO_x abatement in comparison with other methods.