Abstract: As a key device for vacuum metrology,the vacuum conductance element plays an important role in the field of vacuum leakage detection and related measurements.Among the various types of conductance elements,molecular flow-conductance elements have attracted wide attention due to their conductance characteristics.This paper provides a brief overview of several molecular flow-vacuum conductance elements that can obtain ultra-small flow conductance.The content includes anodic aluminum oxide,silicon-based micro-nano channels,and graphene molecular flow-conductance elements.The production process and conductance test results are presented.The upper limit of molecular flow pressure of these molecular flow-vacuum conductance elements is 10⁵Pa.This type of molecular flow-vacuum conductance element with ultra-small conductance can be used in non-evaporable getter performance evaluation,vacuum pump pumping speed testing,vacuum chamber volume determination and leak rate measurement of closed containers.