In this study, the graphene-loaded LaFe1-xCuxO3 nanocomposites (GE/LaFe1-xCuxO3) were prepared by the two-step method. The structure and properties of the samples were represented by X-ray diffractometer (XRD), Fourier-transform infrared spectroscopy (FTIR), Scanning electron microscope (SEM), Transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), and UV–Vis DRS, respectively. The results showed that the GE/LaFe1-xCuxO3 photocatalysts were prepared successfully, and the LaFe0.7Cu0.3O3 particles were effectively decorated on the surface of GE. The UV–Vis DRS test showed the graphene and Cu2+ co-doping modified LaFeO3 photocatalyst had a high absorbance in the whole visible light range (380–780 nm) and the bandgap width of the co-doping materials reduced significantly. The photocatalytic test showed the methylene blue (MB) degradation rate of 3% GE/LaFe0.7Cu0.3O3 under sunlight was 100% within 4 h, which was an increase of 75.4% than that of LaFeO3. The kinetic rate constant of 3% GE/LaFe0.7Cu0.3O3 is 1.07 h−1, which is 5.69 times and 1.97 times higher than that of LaFeO3 and LaFe0.7Cu0.3O3. The synergistic effect of Cu2+ and GE on LaFeO3 promotes the separation of photogenerated electrons and holes, thereby greatly improving the photocatalytic activity of LaFeO3. This work provided a new way to improve the efficiency of treating organic pollutants and broaden the photocatalytic application.