CO methanation reaction over a nanosized NiCo aerogel catalyst (NiCo) for synthetic natural gas production was investigated in a magnetic fluidized bed (MFB) reactor. The results indicated that the NiCo catalyst showed poor fluidization behavior, while the fluidization quality of the catalyst can be greatly improved by introducing an axial uniform magnetic field. The catalyst in the MFB reactor afforded higher conversion of CO and higher selectivity and yield of CH4 than those in the conventional fluidized bed, which was attributed to the MFB reactor improved gas-solid contract efficiency and inhibited axial back-mixing of the product gas. The catalytic performance in the MFB reactor was quite stable during a 100 h reaction. Such good stability is attributed to the superior property of the catalyst and the improved gas-solid contact efficiency in the MFB reactor. Furthermore, the particle agglomeration was inhibited when the catalyst was explored to a magnetic assisted fluidized bed. The combination of magnetic nanosized catalyst and MFB intensification as a promising route was developed for synthetic natural gas production.