K3PW12O40 is a promising polyoxometalate photocatalyst for the removal of organic pollutants from water. However, two main disadvantages of poor adsorptive performance and high recombination rate of photogenerated electron-hole pair hinder its practical applications. In this paper, a new graphene nanosheets/K3PW12O40 nanocomposite has been synthesized via a green photoreduction strategy, being low-cost and scalable production. Characterizations show that K3PW12O40 nanoparticles with 60 nm or so have been successfully deposited on the graphene nanosheets. As a kind of photocatalyst, the binary graphene nanosheets/K3PW12O40 nanocomposite displays improved photocatalytic activity compared to pure K3PW12O40. This improvement is ascribed to the introduction of graphene nanosheets in the nanocomposite, which could increase adsorptive property and reduce the recombination of electron hole pairs. (C) 2016 Elsevier Ltd. All rights reserved.