The geometric configuration，electronic structures and vibrational frequency of the Al2O3Hx(x=1—3) molecules were calculated using B3LYP method at 6-311++g(d,p) level systematically. The calculations give the total energies, zero point energies, mol heat capacities under constant volume, standard entropies, atomization energies, vertical ionization energies, vertical electron affinity energies of their possible ground state structures. The geometric configurations of possible ground state structures of Al2O3H and Al2O3H2 molecules are planar. The geometric configurations of two possible ground state structures of Al2O3H3 molecule are solid geometric configurations which come from the solid geometry of Al2O3 with D3h symmetry adding three hydrogen atoms to oxygen atoms and aluminum atoms. The configurations of these three molecule clusters with lowest energy are: Al2O3H (2A′)Cs, Al2O3H2(1A′)Cs and Al2O3H3(2A)C1.