In this study, an effective hydrogen production for electrochemical ammonia synthesis is performed using a photoelectrochemical hydrogen production reactor. A photoelectrochemical cell is built by electrodepositing photosensitive Cu2O particles on a cathode stainless steel plate. The produced hydrogen is supplied to a molten salt electrolyte‐based electrochemical ammonia synthesis reactor at ambient pressure where nitrogen gas is co‐supplied from a nitrogen tank. Using photoelectrochemically produced hydrogen, the electrochemical synthesis of ammonia is successfully accomplished. The reactions of nitrogen and hydrogen gases occur in a molten salt ambient consisting of molten hydroxides (NaOH and KOH), whereas the reaction temperature is varied in the range of 180°C to 260°C to investigate the impact of temperature on the performance. The porous nickel‐meshed electrodes with an effective area of 25 cm2 are used as cathode and anode. The hydrogen production process is characterized under both concentrated light and non‐concentrated light conditions. The maximum Coulombic efficiency for ammonia synthesis is calculated to be 14.2% with an ammonia production rate of 4.41 × 10−9 mol/s cm2 via nano‐Fe3O4 catalyst. Copyright © 2017 John Wiley & Sons, Ltd.