This paper mainly use glass nanopores to investigate the change of ion current in the crowded condition of macromolecules, finds the relevant factors that affect the change of ion current, and tries to explain the reason for this phenomenon. In the process of investigating the phenomenon of crowding of macromolecules, the experimenters will find that in the case of nanopores, when the crowding of macromolecules reaches a certain level, a special phenomenon of ionic current will occur. No one has proposed a convincing phenomenon for this phenomenon. In response to this phenomenon, members of the experimental group used PEG as a macromolecular crowding agent. For this phenomenon, the relative molecular weight of PEG, PEG content (w/v), electrolyte type, and glass nanopore pore size were carried out correspondingly. Explore and try to explain the change in ion current.