Azo polymer brushes (G-PCN) on graphene nanosheets are prepared through a "grafting-from" approach. The effect of the graphene nanosheets on photoinduced surface modulation is investigated by irradiating solid films of azo molecular glass (Tr-Az-CN) containing the nanosheets with interfering Ar+ laser beams. By formation of a surface-relief grating, a very significant increase in the growth rate and saturated value of the diffraction efficiency is observed for Tr-Az-CN doped with G-PCN at very low content (0.5 wt%).