The integration of graphene with certain metallic nanoparticles, such as Au, Ag, Pt, Pd, Cu, etc., to produce a new generation of hybrid materials is a field of intense research nowadays. Graphene, being a single atom thick layer sheet of hexagonally arranged sp² carbon atoms, has a prodigious number of free electrons, which can be used to reduce metallic ions to produce a hybrid material consisting of metal nanoparticles on the 2D fabric of graphene. Efforts were made to explore such property of the virgin graphene by careful in situ study using UV-visible (UV-vis) spectroscopy and transmission electron microscopy (TEM). The results indicate that it is possible to use surface potential of graphene to reduce Au³⁺, Ag⁺, Pt²⁺, Pd²⁺ and Cu²⁺ ions to prepare graphene–metal nanoparticle hybrids. The extensive TEM studies substantiate the finding of the formation of graphene decorated with metal nanoparticles.