Palladium nanoparticles were supported on magnetic Fe3O4/reduced-graphene oxide(Fe3O4/r-GO) nanohybrid by reduction of dichloropalladium (II) complex in water. Pd/Fe3O4/r-GO nanohybrid was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction, and transmission electron microscopy (TEM). Our study shows that Pd/Fe3O4/r-GO nanohybrid was suitable for Suzuki-Miyaura carbon-carbon coupling reaction in water. Compared to the classical reactions, this method consistently has the advantages of green solvent, short reaction times, little catalyst loading, high yields, easy magnetically separation and reusability of the catalyst. Furthermore, Pd/Fe3O4/r-GO nanohybrid shows a high catalytic activity toward aryl chloride derivatives. (C) 2014 Elsevier B.V. All rights reserved.