Solid state nanopores or nanochannels prepared in polymer[1;2]and semiconductor films[3]have shown interesting transport phenomena,because of their diameters at the nanoscale and positive or negative charges on their walls.Graphene is an ideal material for developing solid state nanopores not only due to its atomic scale thickness,high mechanical strength and chemical stabilities but also because of the impermeability of the pristine single layer graphene to all atoms and molecules except protons[4].As the single Graphene/PET(G/PET)nanopore is the elementary building block for nanoporous membrane,the understanding and control of its individual ionic transport properties are also crucial in protein separation,water desalination,and bio-molecule detection using arrays of identical nanopores.Here,the single G/PET nanopore was successfully prepared by using ion irradiation technology and asymmetric etching method[5]and the corresponding ionic transport properties were investigated in detail.