Graphene, a monolayer of sp 2 hybridized carbon atoms arranged in a two dimensional lattice has attracted electronic industrial interest due to its exceptional electrical properties. One of the most promising applications of this material is in polymer nanocomposites in which the interface of graphene based materials and polymer chains merge to develop the most technologically promising devices. This chapter presents the electrical properties of such graphene based polymer nanocomposites and also discusses the effect of various factors on their electrical conductivity. Graphene enables the insulator to conductor transition at significantly lower loading by providing percolated pathways for electron transfer and making the polymers composite electrically conductive. The effect of processing conditions, dispersion, aggregation, modification and aspect ratio of graphene on the electrical conductivity of the graphene/polymer nanocomposites is conferred.