Integrating components for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) while optimizing their electronic structure is an effective strategy for developing excellent bifunctional catalysts for rechargeable zinc-air batteries (ZABs). In this study, we successfully fabricated Mn0.3Ru0.7O2 nanosheets based on a solid solution oxide using a simple molten salt method. The Mn0.3Ru0.7O2 nanosheets exhibits abundant Ru and Mn sites through the Ru-O-Mn structure, which serve as excellent OER and ORR active centers. Experimental and theoretical studies validate the coccurrence of charge transefer between the Ru-O-Mn bond, modulating the valence state and d-band center of the Mn and Ru, thereby subsequently improving their ORR/OER intrinsic activity. Remarkably, the Mn0.3Ru0.7O2 nanosheets displays superior electropcatalytic performance with a charge/discharge voltage gap (ΔE) of only 0.59 V, which is the best among all reported counterpart catalysts. A rechargeable ZAB utilizing Mn0.3Ru0.7O2 nanosheets achieved a power density of 154 mW cm−2 and a specific capacity of 821 mA h g−1, surpassing that of the commercial Pt/C + RuO2 mixing catalyst. This study offers a new strategy for preparing highly active and durable bifunctional catalysts for rechargeable ZABs.