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Significance The accurate regulation of membrane–nanofluid interfacial interactions in nanoscale channels is of fundamental importance for achieving high membrane filtration performance. However, concurrently attaining ultrafast water permeation and high ion rejection is challenging for current graphene oxide (GO) membranes, owing to the contradictory effect of water–membrane hydrogen-bond and ion–membrane electrostatic interactions. This study demonstrates a methodology of electropolarization to coregulate water–membrane and ion–membrane interactions through a vertical graphene membrane, resulting in a 1–2 orders of magnitude improvement in the water permeation and superior ion rejection over most reported GO membranes, breaking the permeability/rejection trade-off. This study proposes a powerful interfacial electroregulation strategy that can guide the design of nanofluidic membranes and multifunctional membrane-based devices.