Abstract: A new leak artifact based on monolayer graphene membrane with intrinsic defects is proposed.The monolayer graphene, synthesized via chemical vapor deposition method, is transferred onto a porous sintered stainless steel disc and characterized using Raman spectra.The conductance of He, N₂,and Ar is measured employing our home-made test apparatus based on the difference method.The measured conductance implies that the transport of three types of gas enters molecular flow regime at pressures of up to 10⁵Pa.Hence, the flow conductance of any other gas could be determined in case obtaining the conductance of one certain gas.Furthermore, these results also provide porous two-dimensional plain membrane material, such as graphene, with a new application orientation in fabrication of leak artifact.