We present a totally green approach towards the synthesis and stabilization of aqueous graphene dispersions through UV-irradiated reduction of exfoliated graphene oxide (GO). Polyvinyl pyrrolidone (PVP) is used to enhance the dispersibility of reduced graphene oxide (RGO) by one-step functionalization. The proposed method is low cost and easy without using any photocatalysts or reducing agents, which can open up a new possibility for green preparation of stable RGO dispersions in large-scale production.