Aqueous Zn-ion batteries are promising energy-storage devices; however, dendrite growth and undesirable reactions impede their advancement. Herein, we design a Zn-bonded selective ion transport layer with poly(acrylic acid) via O2 plasma treatment. This strategy enhances the wettability of the aqueous electrolyte and adhesion of the polymeric layer between the aqueous electrolyte and Zn anode. The Zn-bonded polymeric nanolayers (ZHPs) capture anionic salts and suppress side reactions. The fabricated Zn@ZHP symmetric cell and Zn@ZHP||ZnV2O5 full cell demonstrate significantly improved cycle stability of 2,200 h at 10 mA cm-2 of 1 mA h cm-2 (compared to 250 h for bare Zn). Additionally, the full cell retains 95% of its capacity at 1 A g-1 after 500 cycles (compared to 75.4% for bare Zn). The ZHP-designed anode also exhibits stable cycling for over 300 cycles at 5 A g-1 in a pouch-type cell. Thus, the functional layer demonstrates considerable potential for enhancing the stability of aqueous metal batteries.