AbstractUntil now, organic electrode materials have been extensively researched and are expected to emerge as a promising rechargeable battery material, with advantages of adjustable structure, and stable electrochemical performance. Herein, we describe the synthesis of tannic acid metal salt [lithium tannic acid (LiTA) and sodium tannic acid (NaTA)] through a facile and mild acid‐base reaction methodology. The LiTA anode delivers a reversible capacity of 151.7 mAh g−1 at 100 mA g−1 and maintains 100.5 mAh g−1 after 100 cycles. Correspondingly, the NaTA anode presents a capacity of 147.7 mAh g−1 at 80 mA g−1 and remains at 79.9 mAh g−1 after 100 cycles. Both materials show good electrochemical behavior as demonstrated by EIS and GITT measured transport dynamics. Furthermore, the ion storage mechanism investigated by ex‐situ FTIR and ex‐situ XPS indicated that the redox pair changes between the C=O and C−O bonds. Therefore, the feasibility of tannic acid metal salt as a rechargeable battery anode provides a strategy to search for other natural organic compounds as promising energy storage materials.