Flexible energy storage plays a crucial role in the field of flexible electronics, because it provides the energy supply, and its technological advancement directly affects the performance and application scope of flexible electronics. As an important flexible energy storage technology member, aqueous zinc (Zn) ion batteries (AZIBs) have garnered considerable attention due to their high safety and low cost. However, the development of flexible AZIBs is hindered by Zn metal anodes (ZMAs), where Zn is prone to growing into dendritic structures, especially in a curved state, and thus leads to battery failure. Herein, we design a robust interfacial layer (RIL) for stabilizing ZMAs in flexible AZIBs, whose introduction constructs uniform Zn ion channels and releases stress accumulation on the anode surface. Various experiments and calculations are employed to verify the effectiveness of RIL in suppressing Zn dendrite at bending states. Furthermore, a Zn|MnO₂ flexible pouch battery with RIL is demonstrated with stable cycling performance during bending. We believe this study provides new possibilities for regulating Zn deposition under bending conditions and extends its application to flexible wearable aqueous metal batteries.