The feasibility of the formation of a liquid plasma catalysis system through micro arc oxidation(MAO) under AC power with titanium-aluminum alloy electrodes was investigated.In the decolorization of organic dyeing wastewater simulated with Rhodamine B,Ti-Al alloy electrodes were superior over Ti electrodes and Al electrodes.The optimal molar percentage of Ti in alloy electrodes was 70%and the optimal decolorization rate was up to 88.9%if the additive suitable for Al was added into the solution to be treated.The decolorization rates were the same in the case of the alloy-alloy electrodes and alloy-Al electrodes.The proportion of the effects of plasma,TiO_2 catalyzer during MAO and H_2O_2 after MAO in decolorization has been obtained.With the catalysis of TiO_2 formed on the electrodes,the reaction rate was improved by a maximum of 95%and the decolorization rate was improved by a maximum of 71.6%.Based on the spectral analysis,the plasma catalysis mechanism has been studied. The feasibility of the formation of a liquid plasma catalysis system through microarc oxidation (MAO) under AC power with titanium-aluminum alloy electrodes was investigated. In the decolorization of organic dyeing wastewater simulated with Rhodamine B, Ti-Al alloy electrodes were superior over Ti electrodes and Al electrodes. The optimal molar percentage of Ti in alloy electrodes was 70% and the optimal decolorization rate was up to 88.9% if the additive suitable for Al was added into the solution to be treated. The decolorization rates were the same in the case of the alloy-alloy electrodes and alloy-Al electrodes. the proportion of the effects of plasma, TiO 2 catalyzer during MAO and H 2 O 2 after MAO in decolorization has been obtained. By the catalysis of TiO 2 formed on the electrodes, the reaction rate was improved by a maximum of 95% and the decolorization rate was improved by a maximum of 71.6%. Based on the spectral analysis, the plasma catalysis mechanism has been studied.