This paper describes the direct conversion of methane on NiO and MgO catalysts supported on a SBA-15 that is a mesoporous support under the plasma discharge. It was seen that the catalysts/SBA-15 were synthesized specifying the well-ordered two-dimensional hexagonal structure. The methane conversion of catalysts/SBA-15 was lower than that of the bare SBA-15. On the other hand, C-2 selectivity of NiO/SBA-15 was higher than that of the MgO/SBA-15, while the bare SBA-15 was the lowest. The methane conversion was different according to whether NiO or MgO catalyst used, which was the similar tendency with their textural properties. The mechanism of the methane direct conversion under the plasma was proposed, which is based on the enhanced activation of methane adsorption on the catalyst through the plasma. The methane vibrationally excited by the plasma can be adsorbed with a low activation energy on the catalyst. In addition, the mesoporous SBA-15 that has a high specific surface area can enhance the vibrational excitation of methane. The FT-IR analysis was performed to verify the proposed mechanism for the interaction of the plasma with the surface of SBA-15 during the direct conversion of methane. As a result, it was confirmed that the catalyst with a high specific surface area enhanced the plasma reaction because the polarity of chemical bonds increased.