High entropy alloys (HEAs) offer promising catalysts for lithium-mediated CO₂ redox reactions due to their tunable electronic and geometric structures. This study presents NiFeCoCuRu HEAs with an average diameter of 2.17 nm, designed to facilitate both CO₂ reduction and Li₂CO₃ decomposition. The HEAs exhibit significant charge redistribution, shifting the d-band center closer to the Fermi level and forming active clusters of Ru, Co, and Ni. This enhances the stability of intermediates like *LiCO₂ and *LiCO₃+CO, improving reaction efficiency and durability. The HEAs demonstrate a low overpotential of 0.82 V and operate for over 2900 hours, outperforming pure Ru catalysts. The study highlights the role of HEAs in providing multiple active sites with varied adsorption energies, enabling efficient CO₂ redox reactions. The HEAs' unique structure and electronic properties, supported by experimental and theoretical analyses, contribute to their superior catalytic performance. The research underscores the potential of HEAs in advancing CO₂ electrochemical conversion technologies.High entropy alloys (HEAs) offer promising catalysts for lithium-mediated CO₂ redox reactions due to their tunable electronic and geometric structures. This study presents NiFeCoCuRu HEAs with an average diameter of 2.17 nm, designed to facilitate both CO₂ reduction and Li₂CO₃ decomposition. The HEAs exhibit significant charge redistribution, shifting the d-band center closer to the Fermi level and forming active clusters of Ru, Co, and Ni. This enhances the stability of intermediates like *LiCO₂ and *LiCO₃+CO, improving reaction efficiency and durability. The HEAs demonstrate a low overpotential of 0.82 V and operate for over 2900 hours, outperforming pure Ru catalysts. The study highlights the role of HEAs in providing multiple active sites with varied adsorption energies, enabling efficient CO₂ redox reactions. The HEAs' unique structure and electronic properties, supported by experimental and theoretical analyses, contribute to their superior catalytic performance. The research underscores the potential of HEAs in advancing CO₂ electrochemical conversion technologies.