ABSTRACT Aqueous zinc metal batteries are hindered by the prominent interfacial issues of the Zn anode, such as dendrite growth and intricate side reactions. The in situ construction of a stable solid‐electrolyte interphase (SEI) to address these issues remains a critical challenge, especially under high current density and harsh temperature conditions. Herein, inspired by the absorption of nutrients through plant epidermis, a gradient biomimetic multilayer self‐assembled SEI is constructed. This multilayer biomimetic SEI integrates an outer hydrophobic layer that repels water molecules to create a water‐poor interface, suppressing hydrogen evolution and facilitating Zn 2+ desolvation. The middle‐crosslinked layer stabilizes the SEI structure and captures SO 4 2− to mitigate side reactions, enabling dynamic interfacial regulation. Meanwhile, the innermost adsorption layer regulates Zn 2+ flux, promoting uniform planar deposition along the (002) crystal plane. Benefiting from the existence of biomimetic gradient SEI, the Zn||Zn cell delivers a cycling life of over 2250 h at 20 mA cm −2 , and at ultrahigh current densities (50 and 100 mA cm −2 ), it delivers 12 250 and 1200 cycles, respectively. Furthermore, the pouch cells coupled with I 2 deliver 1.6 Ah. This bioinspired, customizable multilayer SEI achieves Ah‐scale performance and wide‐temperature adaptability, providing valuable insights into the advancement of practical aqueous batteries.