A one-pot hydrothermal synthesis approach was developed to prepare FeSO₄·(H₂O)–graphene oxide (GO) nanosheets. Au nanoparticles were immobilized onto this support, giving Au/Fe₂O₃–GO nanocomposites. Fe₂O₃–GO supports showed high surface area and thermal stability. The Au/Fe₂O₃–GO and synthesized Au/Fe₃O₄ nanocomposites exhibited high catalytic activity and recyclability for the reduction of 4-nitrophenol.