<p>Zinc-ion batteries (ZIBs) represent a promising class of post-lithium energy storage systems. However, their practical deployment is impeded by critical interfacial instabilities, such as uncontrolled growth of zinc dendrites, adverse parasitic interfacial reactions, and cathode material dissolution. Atomic layer deposition (ALD), renowned for its atomic-scale precision and exceptional conformality, offers a pivotal strategy to mitigate these challenges. This review provides a comprehensive analysis of ALD applications in ZIBs, with a central focus on a critical paradigm shift: from the use of simple passive physical barriers toward multifunctional coatings capable of actively regulating interfacial chemistry and ion transport. It elucidates the mechanisms through which ALD-derived coatings (e.g., Al₂O₃, ZnO, Fe₂O₃) regulate Zn²⁺ flux, suppress hydrogen evolution reactions (HERs), and induce preferential zinc deposition along specific crystallographic orientations (e.g., the Zn (002) plane) to inhibit dendrite formation. Furthermore, it covers ALD strategies for enhancing cathode structural stability against dissolution and collapse, as well as for functionalizing separators to achieve selective ion transport. Finally, it presents critical perspectives on overcoming the cost-scalability trade-off and deepening the mechanistic understanding of structure-property relationships, aiming to guide the rational design of durable and high-performance ZIBs. This paradigm shift represents a fundamental transition in interface design philosophy for high-performance ZIBs.</p>