The electronic structure and optical properties of Fe doped α-Bi2O3 were studied by using the first-principles hybrid functional HSE06 method. The calculation results show that Fe doped α-Bi2O3 has a small structural deformation, the intrinsic α-Bi2O3 has a band gap of 2.69 eV, and Fe doping reduces the band gap of α-Bi2O3(about 2.34 eV). The optical properties show that the absorption range of visible light of α-Bi2O3 is extended by Fe doping, that is, absorption spectrum redshifts, and the optical properties change mainly in the low energy range. Therefore, it provides a theoretical basis for the application of Fe doped α-Bi2O3 in the field of photocatalysis.