Abstract: Dimethylacetamide (DMAC) is a main pollutant of chemical fiber wastewater which has a great impact on the environment. A new process for DMAC wastewater pretreatment, iron-carbon micro-electrolysis combined with Fenton and coagulation-sedimentation, was developed. The results showed that at the optimum conditions of iron filings dosage of 30 g/L, ratio of iron filings to carbon of 1, pH of 2, hydraulic retention time of micro-electrolysis process of 1 h, H₂O₂ dosage of 5 mL/L, pH of 3, hydraulic retention time of Fenton process of 2.0 h, coagulation pH of 9.0, and hydraulic retention time of sedimentation of 40 min, the removal rate of COD_Cr was more than 70%. Through Vis-UV spectral analysis, it was shown that the chromophoric groups —CH₃ and CO were destroyed after the micro-electrolysis reaction, and after the Fenton oxidization, the amino group was destroyed. With this pretreatment process, the macromolecular substances in the wastewater were destroyed and transformed into small molecules, thus laying the foundation for further treatment.