Abstract: A four chamber electrodialysis was used for purifying the contaminated triethylene glycol solution of Changqing Jingbian Gasfield. The run characteristics such as voltage, running time, flow rate in dilute compartment and inflow concentration of TDS were studied. The optimized process conditions were obtained by using response surface methodology on the based of single-factor tests. Under the optimized conditions of voltage of 48.92 V, running time of 128.09 min, flow rate in dilute compartment of 12.00 L/h, the TDS concentration after treatment could reduce from 1968 mg/L to (38.3±1.2)mg/L. Meanwhile, limited current of electrodialysis processing was determined. When flow rate in dilute compartment reached to 12.00 L/h, the limited current was 0.189 A, and the corresponding limited voltage was nearly 66 V. It was proved that some abnormal phenomena such as concentration polarization were not appeared during the triethylene glycol desalination process.