Active nickel-oxide electrodes prepared by electrochemical oxidation-reduction exhibited electro-catalytic activity for the oxidation of diethylene glycol to diglycolic acid in alkaline mediumAtomic force microscopy （AFM），cyclic voltammetry and galvanostatic electrolysis were used to study the surface characterization of active nickel-oxidation electrode and electrochemical performance toward oxidation of diethylene glycolThe results show that nickel-oxide hydroxide layer formed at the surface of electrode behaves as an efficient electro-catalyst for the oxidation of diethylene glycol to diglycolic acid in alkaline mediumThe effects of various parameters such as time of activation，current density，diethylene glycol concentration and medium temperature on the electro-oxidation of diethylene glycol were investigated Depending upon the experimental conditions，the yield of dilycolic acid was 66.7% with the current efficiency of 66.1% and conversion efficiency of 89%