The ethylbenzene dehydrogenation and the oxidation ability of CO2 on the V2O5(001) surface are systematically studied by the density functional theory method. Results show that among all three lattice oxygen sites On V2O5(001): the vanadyl oxygen O(1), the bridge oxygen O(2), and the three-coordinate oxygen O(3), the O(1) site is the active site for the ethylbenzene dehydrogenation. With the production of styrene, the lattice oxygen O(1) is removed by H2O release. As a soft oxidant, CO2 cannot re-oxidize the defected V2O5(001) in time due to the relatively high activation energy, which gradually leads to the deactivation of the catalyst. (C) 2015 Elsevier Ltd. All rights reserved.