Abstract Single‐metal‐site catalysts integrated within covalent organic framework (COFs) combine maximized atomic utilization with tunable porosity and robust coordination environments, enabling efficient CO 2 diffusion, precise active‐site control, and enhanced electron transfer for superior performance in metal‐CO 2 batteries. However, their practical application is limited by structural instability owing to the weak coordination effect of metal and π electron under high redox‐active operating condition. Herein, a p ‐ d orbital hybridization strategy to strengthen metal‐support interaction (MSI) by introducing a sulfur atom with lone‐pair electrons is reported, achieving highly durable Mg‐CO 2 and photo‐assisted Li‐O 2 batteries. The p ‐ d orbital hybridization strategy effectively lowers the reaction energy barrier and steers the reaction pathway toward the formation of flower‐like discharge products, thereby enhancing both the energy conversion efficiency and reversibility of the battery. The Mg‐CO 2 battery with strengthen MSI achieves a high stable operation for over 420 h at an ultralow overpotential of 0.34 V and a high capacity of 50 Ah g −1 , representing the best‐reported performance among Mg‐CO 2 batteries with single‐metal‐site catalyst to date. In situ electrochemical spectroscopy and theoretical studies prove that the strong MSI decreases discharge/charge energy barriers and switches the product morphology from dense, compact films to flower‐like morphology.