The reaction behavior and technological conditions for selective methanation of carbon monoxide in the hydrogen-rich gas over the nickel-based catalyst prepared by sol-gel method were studied.The effects of reaction temperature and space velocity on the process were investigated.The optimum technological conditions were determined by orthogonal tests to be temperature of 280℃ and space velocity of 1800 h-1.Carbon monoxide could be reduced to zero,and the selectivity to hydrogenation of carbon monoxide was over 99% under above conditions,which could completely meet the qualitative requirement of hydrogen for proton exchange membrane fuel cell.