Multi-modality imaging based on multifunctional nanoparticles holds great promise to fundamentally augment the capability of biomedical imaging, for both the diagnosis and therapy of tumor.Herein, we developed a green and facile method to prepare PEGylated,reduced nano-graphene oxide (rNGO-PEG) from covalently PEGylated nano-graphene oxide (NGO-PEG).