A series of ZrO2/Al2O3 composite oxides with different ZrO2 contents were prepared by impregnation method. The NiO/ZrO2/Al2O3 catalysts for CO methanation were prepared and tested in a tubular microreactor under the condition of T = 300-650 degrees C, P = 1.5 MPa, GHSV (gas hourly space velocity) = 10,000 h(-1), and H-2/CO = 3. The results revealed that adding ZrO2 restrains the formation of NiAl2O4, weakens the Ni-Al2O3 interaction, and makes the catalyst more easily reduced, enhancing significantly the activity of catalyst. Especially, among these catalysts, 20Ni/40ZA catalyst with ZrO2 content of 40 wt.% exhibits high CO conversion and CH4 selectivity in a broad temperature region of 300-550 degrees C. Moreover, 20Ni/40ZA performs superior stability than 20Ni/Al2O3. The added ZrO2 also improves the anti-carbon deposition and anti-sintering performance of Ni/Al2O3 catalyst. (C) 2014 Elsevier B.V. All rights reserved.