In　this　work,　TiO2　was　modified　by　doping　the　electron-deficient　B　element,　and　then　the　gas-sensing　response　of　B-TiO2　to　H-2　under　UV　irradiation　at　room　temperature　in　a　N-2　atmosphere　and　the　oxidation　of　H-2　over　B-TiO2　under　corresponding　conditions　were　tested.　It　was　found　that　H-2　would　accept　an　electron　when　adsorbed　on　the　TiO2　surface,　while　H-2　would　donate　an　electron　when　adsorbed　on　the　B-TiO2　surface.　Correspondingly,　H-2　could　not　be　oxidized　over　TiO2,　but　could　be　oxidized　over　B-TiO2.　This　indicated　that　the　oxidation　of　H-2　was　dependent　on　the　electron-transfer　behavior　between　H-2　and　the　surface　of　TiO2　or　B-TiO2.　Based　on　the　relevant　characterization　results,　it　was　proposed　that　H-2　could　accept　an　electron　from　TiO2　due　to　the　higher　Fermi　level　of　TiO2,　while　H-2　could　donate　an　electron　to　B-TiO2　due　to　the　lower　Fermi　level　of　B-TiO2　induced　by　doping　B.　This　indicated　that　the　electron-transfer　behavior　between　H-2　and　TiO2　could　be　changed　by　adjusting　the　Fermi　level　of　TiO2,　while　the　electron-transfer　behavior　would　further　affect　the　photocatalytic　activity　of　oxidizing　H-2.　This　result　shows　that　the　doable　H-2　photocatalytic　oxidation　in　thermodynamics　can　be　controlled　by　a　kinetics　factor　(H-2　losing-an-electron　behavior).　This　work　can　be　applied　to　provide　an　understanding　of　the　photocatalytic　oxidation　behavior　of　other　reactants　over　semiconductor　materials.