The preparation of methanol (CH3OH) from methane (CH4) oxidation has been viewed as a promising technique to obtain liquid fuel from natural gas. It was demonstrated that oxygen was adsorbed on single palladium (PdO) as an excellent catalyst for the CH4-to-CH3OH conversion under the scheme of density functional theory. The catalyst PdO loaded on boron sheet shows excellent stability and CH3OH selectivity. Computational calculations reveal that the boron substrate re-markably tunes the state of palladium.