The roles of hot electron flow and metal-oxide interfaces in catalytic activity and selectivity are important issues in heterogeneous catalysis. In spite of its importance in fundamental understanding electronic excitations on the surface, there has been no report showing the relation between the hot electron flow and catalytic selectivity. We have observed a significant increase of hot electron flux with methyl formate creation and managed to explain this phenomenon with DFT calculation. Based on these results, we introduce the intrinsic relation between methyl formate selectivity and the hot electron flux in methanol oxidation.