A novel Sm-doped BiOBr/reduced graphene oxide (RGO) composite photocatalyst was synthesized by the solvothermal method using methanol as solvent. The crystallanity, morphology, and chemical compositions were examined using XRD, TEM and SEM-EDAX. The photocatalytic ability of prepared sample was investigated using methyl orange (MO). The results show that Sm-BiOBr/RGO is an excellent photocatalytic material better than pure BiOBr and BiOBr/RGO composite. The enhancement might be ascribed to the higher adsorption of dyes, effective charge separation efficiency and retardation of recombination rate due to Sm doping and RGO incorporation.