The behaviors of FeOx-containing CaO-Al2O3-SiO2 slags under the constant current field were investigated in this study. Electrolysis reaction of molten slag was occurred when exerting electric field between the molybdenum cathode and graphite anode. The current efficiency was calculated to be varied from 10% to 50% at 1400 degrees C for the slags with a low basicity. However, when the basicity of slag is high, the current efficiency can as high as 63% at 1600 degrees C. Furthermore, there is also a higher electrolysis rate for slag with a higher basicity. The experimental results also show that both the current efficiency and electrolysis rate increase as increasing electrolysis current at the constant temperature, while when the current is fixed, the higher the temperature is, the higher the current (C) 2015 The Electrochemical Society. All rights reserved.