Abstract: In the application of vacuum technology，flow limiting element conductance is mainly used for producing tiny gas flow of gas micro-flow meter，providing standard dynamic pressure for vacuum system and calibration of vacuum leak.Measurement methods for orifice conductance consist of constant pressure method，constant volume method，flow comparison method，linear vacuum gauge method and pressure increasing method.This article introduces the applicable scope of four commonly used methods.The application of various measurement methods and their restrictions are enumerated，and compares the characteristics of different measurement methods.