The effects of different concentrations of Fe doping on the photoelectric properties of two-dimensional (2D) CuI semiconductor are studied based on the first-principles calculation method. The results show that both intrinsic 2D CuI and Fe-doped 2D CuI are direct band gap semiconductors. The total state density and partial wave state density of 2D CuI doped with different concentrations of Fe show that the increase in the number of energy bands at Fermi level is due to the influence of Fe-d and Fe-p orbital contributions after Fe doping, which can improve the conductivity of 2D CuI. With the increase of Fe doping concentration, the peak value of ε₁ decreases gradually, and the peak value moves toward the high-energy end near the relatively high energy 3 eV and 6 eV, and the greater the concentration, the more obvious the shift is. These results indicate that Fe doping can enhance the high temperature resistance of 2D CuI. When a small amount of Fe is doped, the ε₂ peak value increases, indicating that the ability of material to absorb electromagnetic waves is enhanced, which can stimulate more conductive electrons, and with the increase of Fe doping concentration, the absorption capability decreases, so the conductivity of 2D CuI is inhibited. The absorption coefficient of intrinsic 2D CuI and Fe-doped 2D CuI indicate that the semiconductor has strong ability to absorb photons in the ultraviolet region. The 2D CuI reflection coefficient of doped Fe atoms increases gradually with the increase of metallic properties of doped elements. This study provides theoretical reference for applying the 2D semiconductor materials and 2D CuI to optoelectronic devices. All the data presented in this paper are openly available at https://doi.org/10.57760/sciencedb.j00213.00060.