In our continuing effort to investigate the effect of non-thermal plasma on CH4/CO2 reforming catalysts, Ni/Al2O3-MgO nanocatalyst is investigated. The impregnated and plasma treated nanocatalysts are characterized using XRD, FESEM, TEM, EDX Dot-Mapping, BET, TG-DTG, XPS and FTIR techniques. XRD patterns show high dispersion and strong interaction of active phase. FESEM images display smaller particle size and a narrow particle size distribution for plasma treated sample. According to the BET analysis, the calculated surface area of plasma treated sample is 11% higher. TEM images show particles of active phase are fairly small and well-dispersed as a result of plasma treatment. XPS and EDX analysis reveal better dispersion of active phase as a result of plasma treatment. In addition to better structural and physicochemical properties, the Ni/Al2O3-MgO nanocatalyst which treated by non-thermal plasma has higher activity and significant anti-coke properties in the CH4/CO2 reforming reaction at 550-850 degrees C temperature range using a mixture of CH4:CO2 = 0.5-2. (C) 2014 Elsevier B.V. All rights reserved.