In this study, Ni/Y_2Zr_2O_7 catalysts prepared with impregnation method and treated by dielectric barrier discharge plasma(DBD) in different atmospheres have been investigated for methane dry reforming. It is revealed by H_2-TPR that plasma treatment can enhance the interaction between Ni O/Ni particles and the Y_2Zr_2O_7 pyrochlore support. Therefore, catalysts with smaller Ni O and Ni grains sizes, higher metallic Ni active surface areas can be achieved, as evidenced by XRD, TEM and H_2 adsorption-desorption measurements. As a consequence, the plasma-treated catalysts show significantly improved activity, stability and coke resistance, as testified by the TEM and TGA-DSC results. Plasma treatment in H_2/Ar gas mixture is found to be the best condition to prepare Ni/Y_2Zr_2O_7, which can be used to obtain a catalyst with the highest activity, stability and most potent coke resistance. It is believed that the smaller Ni grain size and higher metallic Ni active surface area induced by plasma treatment are the inherent reasons accounting for the promoted reaction performance of the Ni/Y_2Zr_2O_7 pyrochlore catalysts. In this study, Ni / Y_2Zr_2O_7 catalysts prepared with impregnation method and treated by dielectric barrier discharge plasma (DBD) in different atmospheres have been investigated for methane dry reforming. It is revealed by H_2-TPR that plasma treatment can enhance the interaction between Ni O / Ni particles and the Y_2Zr_2O_7 pyrochlore support. Thus, catalysts with smaller Ni O and Ni grains sizes, higher metallic Ni active surface areas can be achieved, as evidenced by XRD, TEM and H_2 adsorption-desorption measurements. As a consequence, the plasma -treated catalysts show significantly improved activity, stability and coke resistance, as testified by the TEM and TGA-DSC results. Plasma treatment in H 2 / Ar gas mixture was found to be the best condition to prepare Ni / Y_2 Zr 2 O 7, which can be used to obtain a catalyst with the highest activity, stability and most potent coke resistance. It is believed that the smaller Ni grain size and higher metallic Ni active surface area induced by plasma treatment are the underlying reasons accounting for the promoted reaction performance of the Ni / Y_2Zr_2O_7 pyrochlore catalysts.