In this study, we present a simple and effective approach to the in situ decoration of gold nanoparticles on graphene nanosheets (AuNPs@GNs), employing graphene oxide (GO) as precursor and poly(diallyldimethylammonium chloride) (PDDA) as environmentally friendly reducing agent and stabilizer. The microstructures of as-prepared GO and AuNPs@GNs were characterized in detail. The results confirmed that the high dispersion of AuNPs with mean particle size around 4.1 nm on the surface of graphene nanosheets (GNs) could be easily obtained via using PDDA as reductant; moreover the AuNPs@GNs hybrids exhibited excellent electrochemical activity. This work presents a facile approach to synthesize GNs and opens up a new possibility for preparing graphene and graphene-based nanomaterials for large-scale applications. Crown Copyright (C) 2012 Published by Elsevier B. V. All rights reserved.