This work deals with the catalytic performance of nickel-cobalt supported on ceria-doped gadolinia (GDC) catalyst in the single and in the simultaneous methanation of carbon monoxide and carbon dioxide. The catalysts have been prepared by impregnation method, starting from metal salts precursors. Samples have been characterized by x-ray diffraction (XRD), thermogravimetric analysis and differential scanning calorimetry (TGA-DSC), hydrogen temperature programmed reduction (TPR-H-2), transmission electronic microscopy (TEM), and scanning electron microscopy (SEM/EDX) technique. The temperature examined for methanation tests ranged from 200 degrees C-600 degrees C. The results show that the prepared and optimized catalysts possess the main characteristics of materials suitable for SOECs (solid oxide electrolyzer cells) applications: high metal content (50% wt/wt with respect to the support), high activity, and high stability. The catalytic performance of bimetallic catalysts highlights that the cobalt does not improve the activity of the nickel catalysts.