To provide a nitrogen oxide treating material, with which nitrogen oxides can be efficiently removed without generating subsidiary waste materials.

The nitrogen oxide treating material is, for example, of a powdery state and contains particles obtained by using an ore containing vermiculite as a raw material. Further, the preferable nitrogen oxide treating material contains KOKUBOKUDO, an acidic soil. The amount of nitrogen oxides contained in a material to be treated is reduced or the nitrogen oxides are removed from the material to be treated by treating the material to be treated with the nitrogen oxide treating material.