Abstract: Wet-spun acrylic fibre wastewater was pretreated by Fe-C microelectrolysis reactor process. The effects of iron dosage, active carbon dosage and reaction time on the pretreatment results were investigated by single factor experiments. The results showed that the wet-spun acrylic fibre wastewater with initial COD_Cr of 1 076 mg/L, CN^- of 5.50 mg/L could be effectively pretreated by Fe-C microelectrolysis process. The COD_Cr removal efficiency reached above 36.0%, while CN^- removal efficiency reached higher than 90 % under the conditions of both iron and activated carbon dosages 35 g/L, reaction time 90 min, pH 4.50. The process was effective and easy to control. The BOD₅/COD_Cr ratio was increased from 0.39 to 0.56, so the biodegradability of wastewater was increased significantly.