Graphene-based nanocomposites have attracted considerable attention in numerous fields because of their low mass density, high specific surface area, excellent compatibility, and adequate flexibility. Several research groups have explored the fabrication of these polymer composites with innovative and enhanced characteristics. This chapter summarizes the graphene polymers' electrical, thermal, and mechanical properties. A detailed review of prospective applications of the synthesized graphene-polymer nanocomposites is presented in countless sensor applications such as conversion and energy storage devices, water purification, drug delivery, and photovoltaic cells.