Electrochemical reduction of samarium triiodide (SmI3) into samarium diiodide (SmI2) is investigated as a model reaction to reuse samarium compounds in catalytic ammonia production under ambient reaction conditions. Potentiostatic electrolysis of SmI3 with carbon electrode as a cathode in the presence of bis(trifluoromethylsulfonyl)imide anion based ionic liquids as electrolytes in tetrahydrofuran gives SmI2 in high yields with a high Faradaic efficiency.