Graphene is currently attracting a lot of interest because of their potential applications in several different fields. Various approaches are being developed to prepare it at large-scale, by green method and cost-effectively. To this end, graphene sheets can be prepared by electrochemical exfoliation of graphite in aqueous electrolyte. In this work, graphene was produced by electrochemical exfoliation of graphite in acidic and neutral electrolytes. With this procedure, graphene sheets with low oxygen content are produced. Graphene sheets were also functionalized during the electrochemical exfoliation process by using appropriate reagents and experimental conditions. The resulting materials were characterized by several techniques such as Fourier transform infrared, X-ray photoelectron and Raman spectroscopy, thermogravimetric analysis, elemental analysis, electronic conductivity measurements and electrochemical techniques.