Cyclohexanone oxime, an important feedstock in nylon-6 production, is conventionally synthesized through cyclohexanone-hydroxylamine (NH2OH) and cyclohexanone ammoxidation methodologies. These strategies require complicated procedures, high temperatures, noble metal catalysts, and toxic SO2or H2O2 usage. Here we report a one-step electrochemical strategy to synthesize cyclohexanone oxime from nitrite (NO2−) and cyclohexanone under ambient conditions using a low-cost Cu-S catalyst, avoiding complex procedures and H2O2 usage. 92% yield, 99% selectivity, and 26% Faradic efficiency of cyclohexanone oxime are achieved. The reaction undergoes a NO2-→ NH2OH→oxime reaction pathway. The amplified electrolysis experiment and techno-economic analysis confirm the practical potential of our method. This study opens a mild, economical, and sustainable way for the alternative/complementary production of cyclohexanone oxime.