Reduced graphene oxide/polypyrrole (RGO/PPy) conductive composites were prepared by in-situ oxidative polymerization of pyrrole monomer in the presence of RGO under acidic condition. RGO used for the polymerization was previously prepared from natural graphite using modified Hummer's method, subsequently reduced using hydrazine hydrate. The structural, morphology and electrical property of the composites together with graphene oxide (GO) and RGO were characterized using FTIR, XPS, TGA, HRTEM and XRD. It was observed that the RGO and PPy formed a uniform composite with the PPy layers wrapped on the RGO surface. XRD results showed that the RGO/PPy composite was amorphous as neat PPy, suggesting the backbone structure of the PPy was not damaged by the introduction of RGO. Furthermore, the thermal and electrical properties of the composites were much higher than that of pure PPy thank of RGO.