A detailed chemical kinetic model of aluminum oxidation in gas phase has been constructed. Quantum chemical calculations are performed for obtaining molecular structures of intermediates on the reaction pathways. DFT level calculation is applied to search intermediates and transition states, and CBS-QB3 method is applied to calculate highly accurate potential energies. The rate coefficients of each reaction paths were also calculated based on VTST or RRKM theory for constructing the detailed chemical kinetic model. 76 elementary reactions were investigated for AlxOy intermediates, and chemical kinetics analysis was performed to find the major route of oxidation to Al8O12 as the final product of this model. The mainstream of oxidation and formation of large size AlxOy molecules were discussed on the model, and it was found that AlO, Al2O, and Al2O2 are important intermediates to form Al2O3 or Al2O4 as precursors for Al4O6. (C) 2020 The Combustion Institute. Published by Elsevier Inc. All rights reserved.