We report the preparation and characterization of Ni nanoparticles supported on barium hexaaluminate (BHA) as CO methanation catalysts for the production of synthetic natural gas (SNG). BHA with a high thermal stability was synthesized by a coprecipitation method using aluminum nitrate, barium nitrate, and ammonium carbonate as the precursors. The Ni catalysts supported on the BHA support (Ni/BHA) were prepared by an impregnation method. X-ray diffraction, nitrogen adsorption, transmission electron microscopy, thermogravimetric analysis, H 2 temperature-programmed reduction, O 2 temperature-programmed oxidation, NH 3 temperature-programmed desorption, and X-ray photoelectron spectroscopy are used to characterize the samples. The CO methanation reaction was carried out at pressures of 0.1 and 3.0 MPa, weight hourly space velocities (WHSVs) of 30-%000, 120-%000, and 240-%000 mL·g -1·h -1, with a H 2/CO feed ratio of 3, and in the temperature range 300-600 °C. The results show that although the BHA support has a relatively low surface area, Ni/BHA catalysts displayed much higher activity than Al 2O 3-supported Ni catalysts (Ni/Al 2O 3) with a similar level of NiO loading even after high temperature hydrothermal treatment. Nearly 100% CO conversion and 90% CH 4 yield were achieved over Ni/BHA (NiO, 10 wt %) at 400 °C, 3.0 MPa, and a WHSV of 30-%000 mL·g -1·h -1. Long time testing indicates that, compared to Ni/Al 2O 3 catalyst, Ni/BHA is more stable and is highly resistant to carbon deposition. The superior catalytic performance of the Ni/BHA catalyst is probably related to the relatively larger Ni particle size (20-40 nm), the high thermal stability of BHA support with nonacidic nature, and moderate Ni-BHA interaction. The work demonstrates BHA would be a promising alternative support for the efficient Ni catalysts to SNG production.