Abstract: The electrolysis of the wastewater in the dyestuff factory and the simulated organic wastewater was investigated with a Ti-based IrO₂-Ta₂O₅ coating electrode produced by a pyrolytic process and a ternary oxide electrode with addition of Sn and Pb, respectively. COD experimental results showed that organic components in the wastewater could be decomposed electrolytically by using the IrO₂-Ta₂O₅/Ti electrode. With the electrolysis time increasing, the COD value dropped. The electrolytic efficiency was high at high COD values. At low COD values, adding NaCl into the organic wastewater had a good promotive effect on the electrolytic decomposition of organic components. Adding the third elements, Sn and Pb, into the electrodes could promote the electrolytic decomposition of organic components in the wastewater. The COD decomposition rate of electrolyzing the wastewater increased by 11.2% by using the PbO₂/IrO₂-Ta₂O₅/Ti electrode compared with that by using the IrO₂-Ta₂O₅/Ti electrode.