Abstract Despite recent achievements in the co‐reduction electrosynthesis of urea from nitrogen wastes and CO 2 , the selectivity and yield of the products remain fairly average because of the competition of the NITRR, CO 2 RR, and HER. Here, a strategy involving FeNC catalysts disperse with oxygen‐vacancy‐rich CeO 2 (FeNC‐Ce) is illustrated, in which the reversible hydrogenation of defects, and bimetallic catalytic centers enable spontaneous switching between the reduction paths of NO 3 − and CO 2 . The FeNC‐Ce electrocatalyst exhibits an extremely high urea yield and Faraday efficiency (FE) of 20969.2 µg mg −1 h −1 and 89.3%, respectively, which is highly superior to most reported values (maximum urea yield of 200–2300 µg mg −1 h −1 , FE max of 11.5%–83.4%). The study findings, rationalize by in situ spectroscopy and theoretical calculations, are rooted in the evolution of dynamic NITRR and CO 2 RR co‐reduction involving protons, alleviating the overwhelming single‐system reduction of reactants and thereby minimizing the formation of by‐products.