The electrochemical reduction of nitric oxide (NO) in an aqueous electrolyte was studied using different metal electrodes and gas diffusion electrodes (GDEs). The reduction product selectivity for NO reduction depends strongly on the type of electrode metal. NH3 was produced as the predominant reduction product on Ti, Ni, Cu, and Ag electrodes and N-2,was produced predominantly on a glassy-carbon electrode. The current-potential curve in the NO atmosphere depended on the nature of the metal electrode. Product selectivity did not depend on the metal in electrolysis using GDEs. The predominant product was N2O and N-2, on GDEs containing Ni, Pt, and Cu electrocatalysts.