This review summarizes recent advances in non-noble-metal bifunctional electrocatalysts for zinc-air batteries (ZABs), focusing on design principles and mechanisms. The review discusses the working mechanisms of ZABs, emphasizing the structure-performance relationship of electrocatalysts and the reaction pathways of oxygen redox reactions. It also addresses the challenges and prospects of designing advanced non-noble-metal bifunctional electrocatalysts for high-performance ZABs. ZABs are promising energy storage systems due to their high theoretical energy density, safety, and environmental friendliness. However, the slow multi-step oxygen reaction and reliance on noble-metal catalysts hinder their practical applications. Therefore, efficient and cost-effective non-noble-metal electrocatalysts are needed to enhance the oxygen catalytic reaction. The review discusses the design of bifunctional electrocatalysts from the perspectives of morphology, crystal structure, interface strategy, and atomic engineering. It also includes theoretical studies, machine learning, and advanced characterization technologies to provide a comprehensive understanding of the structure-performance relationship of electrocatalysts and the reaction pathways of oxygen redox reactions. The review highlights the importance of morphology design, crystal structure tuning, interface strategy, and atomic engineering in the development of efficient and durable electrocatalysts. It discusses the advantages of different morphologies, such as zero-dimensional, one-dimensional, two-dimensional, and three-dimensional structures, and their impact on catalytic performance. The review also covers the role of crystal structure in electrocatalysis, including the influence of different crystallographic facets and the effects of amorphization on catalytic activity. It discusses the importance of interface strategies in enhancing catalytic performance, including the development of heterointerfaces and the optimization of reaction pathways. Finally, the review discusses the challenges and future prospects of designing advanced non-noble-metal bifunctional electrocatalysts for ZABs, emphasizing the need for further research to improve the performance and stability of these catalysts.This review summarizes recent advances in non-noble-metal bifunctional electrocatalysts for zinc-air batteries (ZABs), focusing on design principles and mechanisms. The review discusses the working mechanisms of ZABs, emphasizing the structure-performance relationship of electrocatalysts and the reaction pathways of oxygen redox reactions. It also addresses the challenges and prospects of designing advanced non-noble-metal bifunctional electrocatalysts for high-performance ZABs. ZABs are promising energy storage systems due to their high theoretical energy density, safety, and environmental friendliness. However, the slow multi-step oxygen reaction and reliance on noble-metal catalysts hinder their practical applications. Therefore, efficient and cost-effective non-noble-metal electrocatalysts are needed to enhance the oxygen catalytic reaction. The review discusses the design of bifunctional electrocatalysts from the perspectives of morphology, crystal structure, interface strategy, and atomic engineering. It also includes theoretical studies, machine learning, and advanced characterization technologies to provide a comprehensive understanding of the structure-performance relationship of electrocatalysts and the reaction pathways of oxygen redox reactions. The review highlights the importance of morphology design, crystal structure tuning, interface strategy, and atomic engineering in the development of efficient and durable electrocatalysts. It discusses the advantages of different morphologies, such as zero-dimensional, one-dimensional, two-dimensional, and three-dimensional structures, and their impact on catalytic performance. The review also covers the role of crystal structure in electrocatalysis, including the influence of different crystallographic facets and the effects of amorphization on catalytic activity. It discusses the importance of interface strategies in enhancing catalytic performance, including the development of heterointerfaces and the optimization of reaction pathways. Finally, the review discusses the challenges and future prospects of designing advanced non-noble-metal bifunctional electrocatalysts for ZABs, emphasizing the need for further research to improve the performance and stability of these catalysts.