Achieving a high rate of ionic transport through porous membranes and ionic channels is important in numerous applications ranging from energy storage to water desalination, but still remains a challenge. Herein we show that ions can quickly pass through interlayer spaces in hydrated boron nitride (BN) membranes. Measurements of surface-charge governed ionic currents through BN conduits in a variety of salt solutions (KCl, NaCl and CaCl 2) at low salt concentrations (<10-4 M) showed several orders of magnitude higher ionic conductivity compared to the bulk solution. Moreover , due to the outstanding chemical and thermal stability of BN, the ionic conduits remain fully functional at temperatures up to 90°C. The BN conduits can operate in acidic and basic environments, and do not degrade after immersing in solutions with extreme pH (pH~0 or 14) for one week. Those excellent properties make the BN ionic conduits attractive for applications in nanofluidic devices and membrane separation.