Supported nickel catalysts have been extensively applied in the industrial process of steam reforming of methane because of the high activity and plentiful resources of nickel.However,the nickel based catalyst has a high thermodynamic potential to coke formation during the reaction[1].Here we use a dielectric barrier discharge(DBD)plasma to decompose nickel nitrate to prepare Ni/SiO2 catalyst which can significantly reduce coke formation for methane steam reforming.Compared with the thermally prepared Ni/SiO2 catalyst,the DBD plasma prepared sample has smaller crystallite size,less defect sites and enhanced metal support interaction.