Electrochemical C-N coupling of CO₂ with nitrogenous sources (e.g., N₂, NO₃⁻) provides a promising method for urea production, whereas the current electrochemical methods are limited by low conversion efficiency or reliance on fossil fuel-derived NO₃⁻ feedstock. Here, we develop a plasma-electrocatalytic route for urea synthesis from ambient air and CO₂, which starts with plasma-assisted air activation to generate reactive NO_x⁻ (92.1% NO₂⁻), followed by electrocatalytic co-reduction of CO₂ + NO_x⁻ to urea. By using a single-atom Ru₁/CuO_x catalyst in double chamber membrane electrode assembly, we achieve a urea yield rate of 106.9 mmol h⁻¹ g_cat⁻¹ and a Faradaic efficiency of 86.7%. This plasma-electrocatalytic route demonstrates a paradigm-shifting strategy for revolutionizing urea synthesis, making a great leap toward decarbonized nitrogen economy.