Atmospheric　water　harvesting　(AWH)　has　been　broadly　exploited　to　meet　the　challenge　of　water　shortage.　Despite　the　significant　achievements　of　AWH,　the　leakage　of　hydroscopic　salt　during　the　AWH　process　hinders　its　practical　applications.　Herein,　inspired　by　the　unique　selective　permeability　of　the　phospholipid　bilayer,　a　sandwich　structural　(hydrophobic-hydrophilic-hydrophobic)　polyacrylonitrile　nanofibrous　membrane　(San-PAN)　was　fabricated　for　AWH.　The　hydrophilic　inner　layer　loaded　with　LiCl　could　capture　water　from　the　air.　The　hydrophobic　microchannels　in　the　outer　layer　could　selectively　allow　the　free　transmission　of　gaseous　water　molecules　but　confine　the　hydroscopic　salt　solution　in　the　hydrophilic　layer,　achieving　continuous　and　recyclable　water　sorption/desorption.　As　demonstrated,　the　as-prepared　AWH　devices　presented　high-efficient　adsorption　kinetics　from　1.66　to　4.08　g　g(-1)　at　30%　to　90%　relative　humidity.　Thus,　this　work　strengthens　the　understanding　of　the　water　transmission　process　along　microchannels　and　provides　insight　into　the　practical　applications　of　AWH.