Abstract Li‐CO 2 battery with high energy density has aroused great interest recently, large‐scale applications are hindered by the limited cathode catalysis performance and execrably cycle performance. Herein, Mo 3 P/Mo Mott‐Schottky heterojunction nanorod electrocatalyst with abundant porous structure is fabricated and served as cathodes for Li‐CO 2 batteries. The Mo 3 P/Mo cathodes exhibit ultra‐high discharge specific capacity of 10 577 mAh g −1 , low polarization voltage of 0.15 V, and high energy efficiency of up to 94.7%. Mott‐Schottky heterojunction formed by Mo and Mo 3 P drives electron transfer and optimizes the surface electronic structure, which is beneficial to accelerate the interface reaction kinetics. Distinctively, during the discharge process, the C 2 O 4 2− intermediates combine with Mo atoms to form a stable Mo‐O coupling bridge on the catalyst surface, which effectively facilitate the formation and stabilization of Li 2 C 2 O 4 products. In addition, the construction of the Mo‐O coupling bridge between the Mott‐Schottky heterojunction and Li 2 C 2 O 4 promotes the reversible formation and decomposition of discharge products and optimizes the polarization performance of the Li‐CO 2 battery. This work provides another pathway for the development of heterostructure engineering electrocatalysts for high‐performance Li‐CO 2 batteries.