AlO radicals have attracted widespread attention in the fields of organometallic chemistry, catalytic materials, combustion chemistry and astrophysics. The study of the effects of external radiation on the physical and spectral properties of AlO radicals will help to further understand and enhance their applications in related fields. The density functional theory B3PW91 method is used to optimize the ground state configuration of AlO radicals under different radiation fields (-0.04~0.04 a.u.) at the 6-311+G (3df, 2p) basis level. On this basis, the molecular structure, total energy, energy gap, infrared spectrum, Raman spectrum and ultraviolet-visible absorption spectrum of AlO radicals were calculated by the same method and level. The results show that under the action of external radiation field, the molecular structure changes obviously, and it has a strong dependence on the radiation field. The total energy of the molecule increases slightly and then monotonically decreases with the radiation field (the maximum is -0.03 a.u.). The bond length of molecule hardly changes significantly under the radiation field (-0.04~0 a.u.), but increases monotonously under the radiation field (0~0.04 a.u.). The dipole moment decreases first and then increases (the minimum is -0.03 a.u.). The energy gap increases first, and then stabilizes in the radiation field (-0.02~0.03 a.u.), and then decreases monotonously. The infrared spectra of AlO radicals under 0.04 a.u. radiation field are red-shifted by 74 cm-1, and the corresponding spectral intensity is 80 times that of the non-radiation field. The strong Raman activity of AlO radicals under -0.03 a.u. radiation field is 688 times that of the non-radiation field. The UV-Vis absorption spectra of AlO radicals in the positive radiation field (0~0.04 a.u.) show that the maximum absorption wavelength of 170 nm in the non-radiation field is blue-shifted by 22 nm and the absorption intensity decreases to half, which is consistent with the trend of the absorption wavelength in the negative radiation field (0~-0.04 a.u.). The UV-Vis absorption spectra of AlO radicals in the directional radiation field (0~0.04 a.u.) show that the second maximum absorption wavelength (282 nm) is blue-shifted by 13 nm and the absorption intensity increases by 2.2 times compared with that in the non-radiation field, but in the negative radiation field (0~-0.04 a.u.), the absorption wavelength is red-shifted by 10 nm and the absorption intensity increases by 6.2 times, which exceeds the maximum absorption wavelength intensity in the non-radiation field.